One of the most popular forms of Sit & Go, heads-up is all about non-stop action. There are only two players and they both play until one of them has all the chips and scoops the prize money.
Unlike with a ten-seat table in heads-up you will be paying blinds every hand, and if you don’t loosen up significantly you will rapidly find yourself anteing away, and your opponent will run you over by winning small pot after small pot. For this reason, playing more hands from the button, where you will be in position the whole hand, is essential, as is playing a reasonable number of hands out of position against loose players. Of course this depends largely on the type of player you are up against and the stack sizes you have.
Another big difference from normal Sit & Go’s is the lack of ICM considerations. With only one prize you are essentially playing a cash game freezeout where your chips have a linear value throughout the match. Therefore you should be pushing every small chip edge, unlike in a standard Sit & Go where that is often the wrong decision because it benefits players who aren’t in the hand who have a chance to move up if you get in a confrontation.
Loose, but not that loose
Although aggressive play is beneficial in this type of game, you would be advised to be not quite so aggressive in heads-up Sit & Go's as you would be in a cash game equivalent for a number of reasons.
Firstly, the stacks are shallower from the outset and they decrease as the game develops and the blinds rise, reducing your implied odds and opportunity to win bigger pots. Secondly, as you’re not able to rebuy if you lose a significant portion of your stack, you need to protect a certain chunk of chips. Otherwise you’ll limit your ability to take advantage of a weaker opponent and you’ll have to win multiple pots to take the game down. For these reasons, some caution is advisable in the early stages, unless you develop a decent chip lead and want to press your advantage home.
Situational awareness
When approaching heads-up Sit & Go’s there are some general adjustments you need to make, such as loosening up and playing more hands. However, to judge quite how loose and how many hands you need to play, you need to gauge a number of factors including position, your opponent and the effective stack sizes.
Position is very important in all poker games, but in heads-up play where the blinds are reversed and the button posts the small blind, it is even more so. The player with position will be able to place considerable pressure on an opponent throughout the hand, as long as the stacks remain relatively deep. For this reason you should be raising the majority of your hands on the button to three big blinds and only folding absolutely unplayable hands like 7-2 offsuit, 4-2 offsuit or J-3 offsuit, although against very tight opponents you can raise almost 100% of the time. Equally, against very loose or aggressive ones you should probably tighten up a little bit more (but not too much).
Facing down the button
Out of position you are at a significant disadvantage throughout the hand, particularly when playing deeper stacked at the beginning of the Sit & Go, so you should only play hands with at least moderate strength to negate this effect. A typical hand range would be all pairs, Broadway Aces, suited Aces, suited connectors and any two paint cards. Depending on how your opponent plays you should also reraise some of the time, since he will often have nothing and have to fold (but beware of getting into big pots out of position with marginal hands).
When playing looser players with strong hands making sure you’re reraising is vital as you’ll often get action, while another time to be aggressive out of position is when you have the chip lead and won’t fall too far behind if you lose the pot.
For the most part, however, calling raises is the best option out of position, though this should be balanced by also calling with some big hands like A-A or K-K. On the flop your opponent will usually make a continuation bet when checked to, allowing you to check-call medium-strength hands or strong hands on dry boards, and check-raise strong hands, draws and occasional bluffs.
Whatever your position, you will often have a medium-strength hand after the flop, so you need to think as much as possible about your plan for the whole hand before you make an action. This might mean raising and then checking behind on the flop with a weak pair to avoid being check-raised, double-barrelling scary turn cards, or betting multiple streets for value with a strong hand.
Heads-up play with deeper stacks is all about getting these marginal decisions right, so start getting in your practice now.
Bossing the endgame
During the early part of a heads-up Sit & Go you need to think a lot about position and play many hands. However, when the effective stacks getting shorter due to the blinds going up, you’ll need to revise your game significantly.
With 20-30 big blinds your strategy shouldn’t change that much from before, although you might now want to lower your standard raise size to 2.5 big blinds, especially against an aggressive opponent who likes to reraise all-in a lot. Reraising all-in yourself is also a good strategy against a player who raises the button too much, as they will have to fold the vast majority of the time and it’s a great way to negate their positional advantage. You may also want to consider limping on the button occasionally at this stage to slow the game down and avoid getting in too many big pots.
Getting short-stacked
When the stacks fall into the 15-20 big blind range the above guidelines still apply, but even more so as reraising all-in becomes a less expensive option. Therefore you need to adjust your ranges for raising, folding and limping on the button even more significantly, depending on how your opponent plays, and beware of losing even a couple of medium-sized pots as this will put your chances of winning in peril. At this point calling raises and check-raising all-in on the flop out of position becomes an excellent idea if you hit a decent hand, as the stack sizes are perfect for doing so. This is especially true if your opponent’s range for raising and continuation betting is still quite wide.
With a short stack of below 15 big blinds, and especially as you fall below ten big blinds, aggression is the key and your best option is usually to just move all-in or fold. Most players tend to play too tight at this stage, so remember that whenever your opponent folds you are winning 1.5 big blinds, and even when called you usually have at least 25% equity in the hand. For this reason shoving hands that don’t look that great like J-3 suited or 9-7 offsuit is fine with a ten big blind stack.
If you want to find big blind values for all hands then the The Mathematics of Poker written by Bill Chen and Jerrod Ankenman is a perfect place to start.