Cribbage Flush In The Crib

In cribbage, the probability and maximum and minimum score of each type of hand can be computed.

• Cribbage Flush In The Crib Toddler Bed
• Cribbage Flush In The Crib Queen
• Cribbage Flush In The Crib Cover

Five-card cribbage (called the 'old game'): The two players are dealt five cards each, two of which are discarded into the crib. The crib thus consists of four cards but each hand only three. The first non-dealer is given a three-point start, the play goes up to 31 only once, and the goal is 61. In the above example, note that the J toss is statistically correct even though it means risking a crib flush. Your chance of giving up this rarest of cribbage scores is about 1 in 140 when you toss two cards of the same suit. This represents an added risk of approximately.036 points. Flush Four cards of the same suit in the hand or crib. In the hand, scores four points. Scores an additional point if the cut card is also the same suit. Aug 19, 2017 A flush of four or five cards. For a four-card flush, all four cards must be in the player's own hand, as opposed to being the shared Crib Card. A five-card flush must obviously use all five cards. The number of points is equal to the number of cards in the flush. Four cards of the same suit in hand 4 (excluding the crib, and the starter) Four cards in hand or crib of the same 5 suit as the starter (There is no count for four-flush in the crib that is not of same suit as the starter) His Nobs. Jack of the same suit as starter in hand or crib 1.

Distinct hands[edit]

• There are 12,994,800 possible hands in Cribbage: 52 choose 4 for the hand, and any one of the 48 left as the starter card.

${\displaystyle (\genfrac{}{}{0ex}{}{52}{4})\times 48=12,994,800}$

• Another, and perhaps more intuitive way of looking at it, is to say that there are 52 choose 5 different 5-card hands, and any one of those 5 could be the turn-up, or starter card.
  Therefore, the calculation becomes:

${\displaystyle (\genfrac{}{}{0ex}{}{52}{5})\times 5=12,994,800}$

• 1,009,008 (approximately 7.8%) of these score zero points,^[1] or 1,022,208 if the hand is the crib, as the starter must be the same suit as the crib's four cards for a flush.
• Not accounting for suit, there are 14,715 unique hands.^[2]

Maximum scores[edit]

• The highest score for one hand is 29: 555J in hand with the starter 5 of the same suit as the Jack (8 points for four J-5 combinations, 8 points for four 5-5-5 combinations, 12 points for pairs of 5s and one for his nob).
• The second highest score is 28 (hand and starter together comprise any ten-point card plus all four 5s, apart from the 29-point hand above).
• The third highest score is 24 (A7777, 33339, 36666, 44447, 44556, 44566, 45566, 67788 or 77889).
• The highest score as a dealer from the hand and crib is 53. The starter must be a 5, the hand must be J555, with the Jack suit matching the starter (score 29), and the crib must be 4466 (score 24), or vice versa.
• The highest number of points possible (excluding pegging points) in one round is 77. The dealer must score 53, the opponent must then have the other 4466 making another 24 point hand for a total of 77.
• The highest number of points from a hand that has a potential to be a '19 hand' is 15. It is a crib hand of one suit, 46J and another ten card, with a 5 of that suit cut up. The points are 15 for 6, a run for 9, nobs for 10, and a flush for 15. Any of the following cards in an unlike suit yields a '19 hand'; 2,3,7,8,and an unpaired ten card.
• The most points that can be pegged by playing one card is 15, by completing a double pair royal on the last card and making the count 15: 12 for double pair royal, 2 for the 15, and 1 for the last card. This can happen in two ways in a two-player game. The non-dealer must have two ten-value cards and two 2s, and the dealer must have one ten-value card and 722, in which case the play must go: 10-10-10-go; 7-2-2-2-2. For example:

• Alternatively, the players can each have two deuces, with one also holding A-4 and the other two aces. Then play might go 4-A-A-A-2-2-2-2.
• The maximum number of points that can be scored in a single deal by the dealer in a two player game is 78 (pegging + hand + crib):
  Non-dealer is dealt 3 3 4 4 5 J and Dealer is dealt 3 3 4 4 5 5. Non-dealer discards J 5 to the crib (as ill-advised as this may be). Dealer discards 5 5 to the crib. Note that the J is suited to the remaining 5. The remaining 5 is cut.
  Play is 3 3 3 3 4 4 4 4 go. The dealer scores 29 total peg points.
  The dealer's hand is 3 3 4 4 5 = 20
  The dealer's crib is J(nobs) 5 5 5 5 = 29
  The total score for the dealer is 29 + 20 + 29 = 78.
  Note that the correct play for both players is to keep 3 3 4 5 worth 10 points and discarding J 4 and 4 5 to the crib respectively, meaning in reality, this hand would never take place. A more realistic hand would be both players being dealt 3 3 4 4 J J with both discarding J J and a 5 cut. In this case, with pegging as described above, the total score would be 20 (hand) + 21 (crib) + 29 (pegging) = 70 points.
• The maximum number of points that can be scored in a single deal by the non-dealer in a two player game is 48 (pegging + hand), with the following example :
  Non-dealer is dealt 5 5 4 4 crib crib and Dealer is dealt 4 4 5 9 crib crib. Cut card is a 6.
  Play is 5 5 5 4 4 4 4, with the Non-dealer pegging 24. The Non-dealer scores 24 in the hand for a total of 48 points.
• The maximum number of points that can be scored with a four-card flush is 21, which is achieved with a hand of 5 5 10 J Q or 5 5 J Q K: a pair, six fifteens, a three-card sequence, and the flush. A five-card flush of 5 10 J Q K scores 18 if the Jack is not the starter.

Minimum scores[edit]

• The dealer in two-player, 6-card cribbage will always peg at least one point during the play (the pegging round), unless the opponent wins the game before the pegging is finished. If non-dealer is able to play at each turn then dealer must score at least one for 'last'; if not, then dealer scores at least one for 'go'.
• While 19 is generally recognized as 'the impossible hand', meaning that there is no combination of 5 cards that will produce a score of 19 points, scores of 25, 26, 27, and greater than 29 are also impossible in-hand point totals.^[1] Sometimes if a player scores 0 points in their hand they will claim they have a '19-point hand.'^[3]

Minimum while holding a 5[edit]

If a player holds a 5 in their hand, that player is guaranteed at least two points, as shown below:

A 0-point hand must have five distinct cards without forming a run or a fifteen combination. If such a hand includes a 5, it cannot hold a 10 or a face card. It also cannot include both an A and a 9; both a 2 and an 8; both a 3 and a 7; or both a 4 and a 6. Since four more cards are needed, exactly one must be taken from each of those sets. Let us run through the possible choices:

• If the hand includes a 9, it cannot hold a 6, so it must hold a 4. Having both a 4 and a 9, it cannot hold a 2, so it must hold an 8. Holding both a 4 and an 8, it cannot hold a 3, so it must hold a 7. But now the hand includes a 7-8 fifteen, which is a contradiction.
• Therefore, the hand must include an A. If the hand includes a 7, it now cannot contain an 8, as that would form a 7-8 fifteen. However it cannot hold a 2, as that would form a 7-5-2-A fifteen. This is a contradiction.
• Therefore, the hand must include a 3. Either a 2 or a 4 would complete a run, so the hand must therefore include a 6 and an 8. But this now forms an 8-6-A fifteen, which is a contradiction.

Therefore, every set of five cards including a 5 has a pair, a run, or a fifteen, and thus at least two points.

Interestingly, a hand with two 5s also can score only two points; an example is 2 5 5 7 9, which would be most likely a crib hand, and would not score a flush because of the pair, although said hand can be a non-crib four-card flush if either 5 is the starter. A hand with three 5s scores at least eight points; a hand with all four 5s scores 20 points and is improved only with a 10, J, Q, or K (scoring 28 except for the 29 hand previously described.)

It is also true that holding both a 2 and a 3, or an A and a 4 (pairs of cards adding up to five) also guarantees a non-zero score:

• If a hand includes both a 2 and a 3 and is to score 0 points, it cannot have a face card, an A, a 4, or a 5. This requires three cards from the 6, 7, 8, and 9, and any such selection will include a fifteen.
• If a hand includes both an A and a 4 and is to score 0 points, it cannot have a face card or a 5. It also cannot have both a 2 and a 3; both a 6 and a 9; or both a 7 and an 8. If the hand includes a 2, it cannot have a 9 (9-4-2 fifteen). Thus it must have a 6. It then cannot have an 8 (8-4-2-A fifteen) or a 7 (7-6-2 fifteen). If, however, the hand includes a 3, it cannot include an 8 (8-4-3 fifteen) or a 7 (7-4-3-A fifteen). These are all contradictions, so every hand containing both an A and a 4 scores at least two points.

Odds[edit]

• The table below assumes the card(s) discarded to the crib are randomly chosen. Given this assumption, the odds of getting a 28 hand in a two-player game are about 1 in 170984, and a perfect 29 hand 1 in 3,248,700.^[3]

• However, if we assume that the player will always keep J555 if those cards are included in the hand, the odds of getting a perfect 29 hand starting with a six-card hand are 1 in 216,580, while the odds after discarding from a five-card hand are 1 in 649,740.^[4]

Scoring Breakdown, assuming random discard(s) to the crib^[1]

• Mean = 4.7692
• Standard deviation = 3.1254
• Skewness = 0.9039
• Excess kurtosis = 1.4599

Note that these statistics do not reflect frequency of occurrence in 5 or 6-card play. For 6-card play the mean for non-dealer is 7.8580 with standard deviation 3.7996, and for dealer is 7.7981 and 3.9082 respectively. The means are higher because the player can choose those four cards that maximize their point holdings. For 5-card play the mean is about 5.4.

Slightly different scoring rules apply in the crib - only 5-point flushes are counted, in other words you need to flush all cards including the turn-up and not just the cards in the crib. Because of this, a slightly different distribution is observed:

Scoring Breakdown (crib/box hands only)

• Mean = 4.7348

As above, these statistics do not reflect the true distributions in 5 or 6 card play, since both the dealer and non-dealer will discard tactically in order to maximise or minimise the possible score in the crib/box.

Card combinations[edit]

• A hand of four aces (AAAA) is the only combination of cards wherein no flip card will add points to its score.
• There are 71 distinct combinations of card values that add to 15:

Hand and Crib statistics[edit]

If both the hand and the crib are considered as a sum (and both are drawn at random, rather than formed with strategy as is realistic in an actual game setting) there are 2,317,817,502,000 (2.3 trillion) 9-card combinations.${\displaystyle (\genfrac{}{}{0ex}{}{52}{4})\times (\genfrac{}{}{0ex}{}{48}{4})\times 44=2,317,817,502,000}$

• As stated above, the highest score a dealer can get with both hand and crib considered is 53.
• The only point total between 0 and 53 that is not possible is 51.

Scoring Breakdown

• Mean: 9.50397
• Median: 9
• Mode: 8

See also[edit]

References[edit]

1. ^ ^abcSteven S. Lumetta (2007-05-15). 'Amusing Cribbage Facts'. Archived from the original on 2018-01-16. Retrieved 2008-03-03.
2. ^Tim Wood (2008-08-05). 'All Possible Cribbage Hands'. Archived from the original on 2013-02-09. Retrieved 2008-08-05.
3. ^ ^abWeisstein, Eric W. 'Cribbage'. MathWorld. Retrieved 2008-03-02. All scores from 0 to 29 are possible, with the exception of 19, 25, 26, and 27. For this reason, hand scoring zero points is sometimes humorously referred to as a '19-point' hand.
4. ^Cribbage Corner (2008-05-05). 'Perfect cribbage hand odds'. Retrieved 2008-05-05.

Rationale for not scoring a 4-card crib flush?

I am new to the game of cribbage and am curious about the conspicuously negative rule excluding four-card crib flushes. This rule seems to be begging for a good mathematical explanation. Statistics seems like the right explanation, but the five-card crib flush is very improbable and intuitively does not seem to justify a special rule excluding the four-card flush.

Cribbage flush

A flush in cribbage is 4 or more cards all of the same suit (for example, four diamonds). If you hold 4 cards of the same suit in your hand, you score 4. If the turn-up card is also the same suit, you score 5.

However, in the crib, only a 5-card flush will count (the 4 cards in the crib and the turn-up card must all be the same suit).

See the main cribbage rules page for more information, and also our cribbage scoring chart.

500 Cribbage

What is Five Hundred Cribbage?

I am indebted to Mr Herb Barge who sent me scans of a book written by a distant relative of his in the 30s, Thomas B. Stauff. This book, entitled 'Rules of Play governing '500' Cribbage, Thomas system, a Modern Version of Cribbage', appears to be a fairly radical re-working of the game.

Counting 4-4-4-3-3

Juli emailed us to ask:

could you help solve an argument.
The hand is 4-4-4-3 with another 3 turned up.
I counted 15-2, 15-4, 6pts for the 4s and 2pts for the pair of threes for a total point count of 12.
Is this correct?

Juli,

Exactly right! The 4-4-4 makes 15 two ways, once with each of the 3s. There's a pair royal of 4s (6 points) and a pair of 3s, no runs, flushes or nobs equals 12 points total.

Cribbage rules - the scoring

(Previous section: Cribbage rules - the go)

Having played out all the cards, both players then score their hands, pone first - this time including the turn-up card as part of both hands. The dealer's crib also includes the turn-up. Again, points are scored for 15s, runs, and pairs; you can also score for a flush (all cards of the same suit) - see the cribbage scoring chart below for a handy reference. It is a key part of the rules of cribbage that the non-dealer should score first - at the end of the game, both players may have enough points to win, and the right to score first will determine victory. The cribbage board's positions usually alternate during the game, with first one player leading, then the other. The trick is to be in the first-scoring position when you are close enough to win!

Cribbage flush

If the four cards in your hand are of the same suit, you score four for a flush (a cribbage flush, unlike in poker, doesn't beat three of a kind!). If the starter card is also of the same suit, you score five. However, in the crib you cannot score a four-card flush; all five must be the same suit. These rules occasionally have local variations, so check to make sure which rules are being used. In an official tournament, the American Cribbage Congress rules apply.

Some cribbage rules sites explicitly state that flushes are not scored in cribbage. This is incorrect, at least according to the American Cribbage Congress rules, which are the nearest thing to an official set of rules for cribbage.

Cribbage pairs

2 points are scored for a pair in cribbage, and 6 for a pair royal - that is, three cards of the same rank. This can be considered as 3 different pairs worth 2 points each. Similarly, double pair royal (four of a kind) scores 12 as there are 6 ways of picking two cards from four. You begin to see why mathematicians love this game.

Combinations of cards making 15 score two points each - for example, 8 and 7. As many ways as you can make 15 with your cards, you score 2 points for each of them. For example, 8-7-7-A can make 15 three ways: the 8 and one 7, the 8 and the other 7, and the 7-7-A. Consequently it scores 6 points (for 15s, and a further 2 for the pair of 7s).

Cribbage runs

Runs score as many points as there are cards in them. For example, a four-card run 9-T-J-Q scores 4.

Cribbage nobs

You also score 1 point if you have the Jack of the same suit as the starter card (known as 'his nob' or just 'nobs').

Cribbage scoring chart

You can print out this cribbage scoring chart and keep it handy when you're playing!

Scoring a 29 hand

Dennis writes:

Can you break down the count of 29 as it is supposed to be counted? It seems you are not allowing the Jack to be counted with the 4 5's for another 8 points which would give 36 points.
Please help me with my confusion over this.
Kind Regards.
Newbie

Dennis,

The 29 cribbage hand page does not explain how the score is broken down, so here goes!

We score the 29 hand in the same way as any other: taking 15s first, then pairs, runs, flushes and nobs.

First count 15s. The Jack makes 15 with each of the 5s, that's 4 15s. Also, there are 4 ways of choosing three different 5s to make additional 15s. That's 8 in total, for 16 points.

Then pairs: there are 6 different pairs of 5s, for another 12 points. That's 28 so far.

There are no runs or flushes, so the Jack of nobs gives us a final point for 29.

I hope this helps!

Runs in the play

Ty Nielson emailed to ask:

So, we’re having some controversy in the office over some of the rules of the cribbage game, all being long time players of cribbage and each of us having slight variations in the rules that we want to play. For the rules that I request please answer with the rules that would be played in a traditional cribbage tournament. This is very important, it’s a business full of wrestlers, knife vendors, construction workers and young people, its getting pretty rough around the company deck here if you can imagine.

1. When in play, and three people are playing cards off of one another, and a sequence of cards is thrown (3, 5, 4) do the cards have to be in sequence? Does the above throw represent a run of three for the thrower of the 4?
2. Now assuming that 3,5,4,2 were played…. Do the last three cards have to be in sequence or is this 4 points for the player of the 2?
3. Once this 4 card series is played, if 3,5,4,2,3 is played is this three points because it is the last three cards which must be in sequence? Or is this a double run of 4 for 8 (not counting the pair)?
4. Similarly if the next card played is a 4, will this count as a double double run of four? How would this be counted.
5. What are the specific rules for adding to runs in game play?
6. During tournament cribbage, when the dealer has 4 cards in the crib of the same suit that do not match the lead card which was cut from the deck how does the dealer count his crib? Flush or not?
7. If you have a detailed standard set of rules

Ty, that's a lot of questions! We spoke to Ezra, Cribbage Corner's wrinkled retainer and rules librarian. His rheumy eyes peered over his horn-rimmed glasses as he said:

The most important rule to remember when counting runs in the play is this. 'Each card played scores points for the run it completes.'

To take your first example of 3, 5, 4, the 4 completes a run of 3 so it scores 3. It does not matter if the cards are not in sequence.

If the next player lays a 2, that completes a run of 4, so scores 4.

There are no double or triple runs in the play (those only count when scoring the hand). So if 3,5,4,2,3 is played the last card only completes a run of 4, so it scores 4.

If the next card is a 4, that completes a run of 3 (2-3-4) so scores 3.

If a pair is played, it scores points for a pair but not for a run. For example, 2-3-4-4 would score 2 points for the pair, but it does not complete any runs, so it does not score any run points. Laying a 5 on this does not complete a run, because of the two 4s preceding it, so scores nothing. Remember there are no multiple runs in the play.

Your last question about the flush is simpler to answer. Remember 'No 4-card flushes in the crib'. While you can score a 4-card flush in the hand, in the crib all 5 cards must be of the same suit to score.

While there are no truly official rules for cribbage, the American Cribbage Congress is the recognised governing body for tournament cribbage in the United States and most tournaments worldwide are played according to its rules:

Cribbage Flush In The Crib Toddler Bed

However, most of these relate to handling unusual situations (misdeals, mis-pegging and so on). For a detailed explanation of the mechanics of cribbage play, Pagat.com's Six Card Cribbage page is very useful.

Scoring a flush in the crib

James Walker emailed to ask:

four card flush...I know it counts fourin hand ...BUT does it score four in CRIB ?

There is a special rule for a flush in the crib. Normally, if you have four or more cards of the same suit in your hand, including the turn up card, you can score a flush. In the crib, however, a flush only scores if all four cards AND the turn up are the same suit. In other words, only a 5-card flush counts in the crib.

Cribbage etiquette

Etiquette is important in card games, cribbage more than most. It is regarded as a gentleman's game (naturally, for card-playing purposes, ladies can be gentlemen too). Like most worthwhile things in life, it is surrounded by complicated and often incomprehensible ritual. However, in an important sense the ritual is the game and so you dispense with it at your peril.

Before the game

Determine whether or not Muggins will be played. If you want to play Muggins but your opponent does not, be gracious and honour his wishes. After all, he is doing you a favour by giving up his time to play cards with you. You should also give your opponent his choice of game - five-card cribbage, six-card cribbage, short game, long game, best of three, best of five, and so forth. The wily pegger never passes up a chance to hone his skills and broaden his experience by playing something different from his usual game.

Some players allow a four-card flush in the crib; though this is not standard, it is a not unreasonable variation and makes for slightly higher scores. However you should determine in advance whether this will be allowed.

Various additions to the standard rules of cribbage are sometimes played, especially in tournaments: for example, that one cannot peg out on a go, or other restrictions on scoring. Unless such rules are specifically mentioned you should assume that you are playing standard cribbage. Once the game has started it is too late to change the rules.

The cut

Most official rules of cribbage stipulate a mandatory cut by pone before the deal. It is indeed common practice to make this cut; however, because it is specifically designed to prevent the dealer cheating, some feel it an unnecessary slur on their character. In games like poker, of course, often played with strangers and for high stakes, such measures are essential. Cribbage is a legacy of a more gentlemanly age (notwithstanding the rumours about Sir John Suckling). A gentleman does not imply that another gentleman might not be a gentleman.

Similarly, the rules allow for pone to take the deck and shuffle it himself before the deal. While perfectly legal, this would be an unusual thing to do and implies that the dealer is suspect.

Our own preference is to skip the cut, if only because it saves a little time. However, if pone requests the cut, of course you must grant it.

Pegging

During the pegging, when you play a card, announce the count clearly and follow it by any score you may have made. For example:

Pone: Four.
Dealer: Ten.
Pone: Fifteen five. [pegs]
Dealer: Twenty for two. [pegs]
Pone: Twenty-five for six. [pegs]
Dealer: Go.
Pone: One for the go. [pegs]

Dealer: Seven. And one for last. [pegs]

You should not peg for your opponent unless you have agreed that one of you will peg for both. Conversely, remember to peg your own points!

Scoring

Lay your cards face up in front of you so that everyone can see and check your scoring. Announce the combinations in a set order - usually: fifteens, pairs, runs, flushes and nobs. As you announce each combination point out the cards involved. For example:

'Fifteen-two, fifteen-four; a pair is six; and nobs is seven.'

Familiar fifteen/pair combinations such as Q-Q-5-5 (12 points) should nonetheless be announced individually: 'fifteen-two, fifteen-four, fifteen-six, fifteen-eight, and two pairs is 12'. Simply announcing 'I have 12' saves only a few seconds, and tells nothing about how the combinations are formed - possibly confusing your fellow players. You may miss points yourself if you try to count by recognising whole sets of combinations at once. At the worst say 'Fifteen-eight and two pairs is 12'. No-one will rebuke you for counting carefully and methodically, as long as you do not waste time. Similarly, combinations such as a double run of 3 (8 points) should be announced as 'two runs of three is six, and a pair is eight'.

Speed

Cribbage should be played allegro, ma non troppo. In other words, don't dawdle, but don't rush it either. Presumably you are playing the game for the enjoyment of it, in which case it should be treated as something to be savoured rather than rushed through at maximum speed.

This is not to say that one should play slowly. Save as much time as you can on things which don't require any thought - riffling, shuffling, dealing and cutting should all be done quickly and without fuss. The temptation is always to talk while one is shuffling, to analyse the previous hand, and so on. Avoid this. Shuffle smoothly and silently, then deal. Talk about the game after the game.

The time you save here can profitably be re-invested in thinking about your discards and plays. Take as much time as you need, but no longer than that. Pretending to ponder over ones discard, perhaps hoping to imply that you have an excellent hand, is not only against etiquette but boots nothing - unless your opponent is so intimidated that he resigns on the spot!

Strive to avoid the temptation, if you are losing badly, to slow right down, distract your opponent with chatter, and generally delay the inevitable. Apart from being bad sportsmanship, it delays the moment when you can start a new, and perhaps more successful game. On a strategic note, it is never worth giving up on a game. If you are losing, you should be fighting hard for every point, and striving to avoid a skunk. If you have no chance of avoiding the skunk, strive to avoid the double skunk! There is always work to be done. At the worst, you can use the freedom of this situation to try out new ideas and experimental plays which you would not risk in a game-leading position.

After the game

If you won, don't crow about it. If you lost, don't gripe about it. Either way, thank your opponent for the game. Compliment her on her play if you thought it was good; keep quiet if it wasn't. Insincere compliments are worth no more in cribbage than any other field.

Refrain from long post-mortems. Do not point out your opponent's mistakes or faults unless she specifically asks you for a critique.

How to cheat at cribbage

Cheating in a friendly card game is pointless, and dangerous in any other kind, so we don't recommend it. But it is possible to cheat in cribbage, and it would be wise to know how to spot if someone is trying to cheat you.

One way to cheat at cribbage is to miscount your hand, particularly when counting quickly, and to announce scores that you haven't in fact made. Always check-count your opponent's hand, and don't let them rush you if it is a tricky score to calculate. It is quite possible to make innocent mistakes when counting, but if your opponent repeatedly overcounts her hand, beware.

Over-pegging your score is another form of cribbage cheating. In a fast-paced game it is easy to peg more points than you made. Double-check your opponent's pegging.

Cribbage Flush In The Crib Queen

It is illegal in cribbage to renege; that is, to fail to play a card when the rules say you can. It happens often that your opponent lays down his last card leaving you with several small cards in hand. You must play them all if you can. If your opponent says 'Go', and following the restart of the count lays down a card that he could have played before the Go, this is a renege and against the rules of cribbage. Usually reneging is simply a mistake, but if this happens more than once in a game your opponent may be trying to cheat you. (The penalty in tournament play for reneging is detailed on the renege page.)

Penalties in cribbage

Cribbage Flush In The Crib Cover

In games where anything other than fun is at stake, penalty points usually apply to offences such as glancing at the bottom card, looking into the crib, or moving your opponent's pegs. See our cribbage penalties page for full details of the penalty points that apply in formal play.