The Smart Player’s Introduction To Short Deck Holdem

It has been just over a year since I started my research into Short Deck Poker and, with its recent release on Pokerstars, it seems like a good time to write some introductory strategy material on the game. As part of my new-found resolve to be more direct (and, dare I say it, self-promoting!) in 2019 I have assumed that the reader is smart enough to have figured out the basics for himself. I’m not going to bore you or myself by writing a basic outline of rules, or trivial observations about connected cards and suits pre-flop. Instead we’ll dive right into the nitty-gritty with three key points to help you negotiate this new terrain.

By the end of it the roots of your Short Deck knowledge may not run deep, but you will at least have shoots where others have sand…

With an ante structure at a six-handed table, 7 antes enter the pot as forced bets at the start of every hand. To compare the size of the game to a blind structure equivalent, we simply divide this starting pot size by 1.5.

7/1.5 = 4.67 and so the ante in a six-handed game is equivalent to half the small blind in a 2/5 blind structure game. The reader may already have guessed that Short Deck Ante structure plays bigger than a regular game, but without running the numbers you are unlikely to have realised that it plays almost 5 times the size!

This ratio also gives us an effective way to map the equivalent stack size for some common Ante structure games to a comparable stack counted in big blinds. Six-handed 100 Ante games are effectively 20BB deep, and a 30 Ante game only plays 6BB deep. So if you sit down and drop five stacks at a 100 Ante Short Deck game you have only experienced a 1 buy-in swing. It is easy for a newcomer to the game to lament an apparent bad run of variance after what is a perfectly normal sequence of results for a shallow game. Long-time readers of this blog would expect there to be more to this stack size business for me to bother bringing up such a simple calculation… and indeed there is!

Because when we switch to a 2-handed game the effective blind decreases and the effective stacks increase as 4 players are no longer contributing to the starting pot. A 100 Ante HU game plays at 50BB deep effective stacks. This means that you could start a table comfortably within your bankroll, only to have players join and for the effective stakes to rise rapidly. I have included a handy table below for you to use as a reference so that you don’t get caught in a game too deep for your roll:

With such shallow effective stacks one might hope to mitigate the swings by seeing cheap flops and extracting value from loose recreational players. I introduce a key consideration for building such a strategy in my next point.

With the ante structure of Short Deck Holdem typically offering a player 7:1 on his pre-flop call we should expect to see limping form a large part of most players’ strategies, provided the starting stacks are deep enough to allow this. This may lead you to want to attack players with wide limping ranges but the numbers indicate caution. If you hold J♦J♠ from position #2 and the opener limps in with the top 50% of starting hands, excluding {AA,KK,AK} then his range will look like this:

Against this range, your Jacks have 60% equity, and so the hand looks like a clear candidate for a raise. The problem is that, with four players left to act, there is a 22% chance of one of your opponents waking up with {QQ+,AK}. That range dominates you 63.5%-36.5% and suddenly your Jacks look a lot more shaky. If, on the other hand you were in position #5, there would only be a 6% chance that the Button would wake up with that same {QQ+,AK} range.

Yet the case for the raise gets worse still- it is a wise strategy to protect an early position limping range by including some {QQ+,AK}. If our loose limper chooses to do this with all of his strongest hands then the chances of us facing {QQ+,AK} against at least one player when we are in position #2 jump to 32%. Once you factor in the difficulty of playing Jacks facing multiple callers in position alongside the threat of facing a 3-bet it is clear that the best decision from position #2 is to over-limp yourself.

Having navigated our way to the flop, the new Short Deck player must be hoping for some familiar territory. But you will soon discover that the game plays very differently here also.

In full-deck games, such as NLHE and PLO, 17% of flops are paired and 18.5% of flops permit at least one made straight. This means that about 64% of flops are unpaired and 0-straight. Monochrome boards at least permit top pair plus a flush draw to be a strong hand and they only account for 5% of flops in total. So on 60% of full-deck NL flops top pair looks like a strong hand.

In short-deck games we have to recalibrate our sense of relative hand strength to make any sense of the board. 25% of all flops are paired and 36% of flops permit  at least one straight. Once we factor out the remaining monochrome boards we are left with a paltry 37% of flops which are polychrome, unpaired and 0-straight.

As a consequence most unpaired, unsuited hands which would rely on their high card value to win hands are unplayable in multiway pots. Yet top pair can still be a strong hand on the flop in HU or 3-way pots, despite the terrifying boards that it will encounter. On the boards with made straights, the strong top pairs are those with straight draws to go with them, a phenomenon that makes this game feel more familiar to Omaha players than to No-Limit players. We see below, on the equity list for a number of top pairs facing a decapitated 50% calling range on a Q♥T♦8♣ board, that the Hand vs Range ‘peak’ is at Q♣J♠. Notice that the overcard Jack to the second pair makes Q♣J♠ substantially stronger than Q♣9♠.

Overpairs also fare better on unpaired flops in the Short Deck game. A quick evaluation with the Cardquant Short Deck Calculator will show you that, on a flop of Q♥J♦6♣, the overpair A♦A♣ has 40% equity against top two pair. The equivalent situation in a full-deck NL game leaves the Aces with only 27% equity.

With equities running so close together in low SPR situations Short Deck Hold’em is an intense, action-packed game and the recent surge of interest in the game is no surprise. The opportunity to dive into a new game and rapidly generate strong strategies was exactly the kind of challenge that Cardquant was set up to take on.

The Cardquant poker strategy research institute has a whole suite of in-house software tools to help me to teach my clients strategies that mainstream sources can’t find. At the time of writing, I have made a simplified version of one of these tools, a Short Deck Hold’em Calculator, available for free to readers of this blog. If there is a lot of demand on the server then I may have to put a gate on the calculator so, if you are interested in either 6+ or Triton Hold’em, have a go now!

If you would like to see more Short Deck Hold’em content then let me know in the comments below.