Heads-up SNGs

Heads-up sit-and-gos have always been popular online and are currently available for stakes as high as $5,600. However, if you’re approaching them from a background of standard full-ring sit-and-gos you’ll need to alter your strategy dramatically. With only two players you must post the blinds every hand, meaning you need to drastically increase the number of hands you are playing to avoid being anted away, and be prepared to make tough decisions in many marginal situations.

Size It Up

Hand selection in heads-up play depends mostly on your position, but also on your opponents and the size of the stacks. Typically you’ll start heads-up SNGs with 1,500 chips, which equates to relatively deep stacks of 50 or 75 big blinds. Initially you should be raising most hands on the button in order to put pressure on your opponent and keep picking up the blinds, which means playing marginal hands more often than premium ones and only folding complete rags like 7-3 or T-2 offsuit. Most players will therefore be playing somewhere between 75-100% of hands on the button.

When reraised preflop you need to consider your opponent’s hand range carefully before deciding to call or reraise all-in. This is very dependent on the exact number of big blinds in your respective stacks, as an opponent’s hand range could vary significantly according to stack size. Generally speaking, however, even with a stack of more than 50 big blinds you cannot afford to call reraises with too many speculative hands unless your opponent is three-betting very wide. The implied odds are quite poor postflop compared to a cash game, and if you do flat-call it should be with big suited connectors, big pairs that you wish to trap with, and other hands that are not quite strong enough to go all-in with.

Moving all-in yourself, or deciding which hands to call an all-in with, are often mathematical problems than can be solved – away from the table at least – by programs such as PokerStove. This free download allows you to compare your own hand versus an opponent’s possible hand range, and reveals the odds of your hand winning. Players should make use of this program as much as possible in order to become familiar with the mechanics of the game. With practice, this aspect of heads-up play will become second nature.

There are differing schools of thought as to what size your preflop raises should be. The standard is three big blinds, but it is also viable to min-raise or make it 2.5x, depending on what you feel most comfortable with. Min-raising will encourage action from your opponent and will be preferable if you like playing pots postflop, or if your opponent is particularly tight or aggressive, since you will save chips when stealing his big blind. Raising to 2.5x is also an increasingly popular option, as it cuts down your opponent’s ability to defend correctly, since he is now getting odds of 7-to-3 rather than 3-to-1. It’s still much cheaper than the traditional raise size too, and makes it harder for your opponents to decide whether to defend liberally or not.

Some players also favour a strategy that involves adding in some limps preflop. If you intend to do this it is important to have a very balanced range that involves limping both big and small hands – and limp-reraising with a balanced range too. Since this is very hard to achieve it is generally not recommended, but is a good strategy to shift to against very aggressive or tilting players as a way of countering their style and keeping the pots small.

Keep It Tight

You should avoid calling out of position with marginal hands that can get you into trouble, but against a player who opens very wide you can three-bet bluff to counter this strategy and help get value from your big hands later in the match.

Unlike in cash games, calling is often better than three-betting as you don’t want to risk your stack early and lose leverage over your opponent. Occasionally calling with very big hands like A-A or K-K is helpful to balance the other playable hands you would normally call with like suited Aces and connectors, Broadway cards and small to medium pairs. You can also adjust your strategy once the stacks start to diversify a bit. For example, if you gain a lead of 1,800 to 1,200 you can now reraise more liberally, since the additional 300 chips you have gained give you more leverage over your opponent due to the effective stack sizes.

When you’re in position postflop you should usually continuation bet unless your opponent tends to play back at you a lot. Pot control can also be useful in deeper-stacked heads-up play, but is only necessary against more sophisticated opponents who are constantly putting pressure on you. If your opponent responds fairly straightforwardly to continuation bets (i.e. he folds weak hands and raises or calls with strong hands), your best option is to bet-fold a lot of your marginal holdings, since you will usually be behind when called or raised. Only exercise pot control on draw-heavy boards where you may be up against a flush or straight draw. In fact, trying to exert pot control against predictable opponents when you have a weak hand will often leave you in a difficult spot, since many opponents will automatically bet the next street with a wide range of hands if you check behind on the flop.

Therefore, you should also try to think ahead about how you want to play a hand and whether you want to try to get to showdown cheaply or go for maximum value. When playing deep-stacked you should also think about more simple eventualities, such as if you bet and are raised or if you check and certain cards come – this line of thinking will help you avoid a lot of tough spots.

On The Range

The most important tools for heads-up play are a good understanding of poker theory and relative hand values heads-up, and the ability to learn and adapt to your foes. Out of position your opponent always acts last, and in deeper-stacked games will be able to fire three barrels at you most of the time. In order to counter this you should have already selected a stronger range of hands to play and folded most garbage, so this should begin to limit the tough situations you can get into. Then you will need to continue applying some poker theory, hand reading and opponent reading to your situation, and think through your plan for each hand.

With most of your medium strength hands you should be calling continuation bets to gain value from worse hands and future bluffs, and polarising your check-raises to strong hands, draws, complete bluffs, and hands with some value that will be hard to win with at showdown. You need to bear in mind your opponent’s raising and c-betting frequencies in doing this, as well as his expected turn and river strategies. As the hand progresses you will need to readjust this hand range and consider your options based on the range you have assigned.

If you are playing in a reraised pot where you three-bet and were called, you need to consider hand ranges and stack sizes again. Typically, leading out on the flop with a bet of around half the pot is a standard line. However, against aggressive opponents or on terrible flops that miss your hand, you should consider checking so as not to be too predictable, and also check with very strong hands and draws that you want to trap or check-raise with. If you have reraised with an awkward hand like 9-9, it may also be preferable to check-raise some awkward flops, such as those with one non-Ace overcard on them, rather than bet-fold or bet-call, if your opponent is likely to take a stab at the flop when you check.

Get Shorty

As the blinds increase and one player gains a lead you will find yourself playing with shallower stacks and have to adapt accordingly. With 15-30 big blinds, limping and reraising all-in become more viable strategies, as well as lowering your opening raise size to 2.5 big blinds or even a min-raise. Once you drop below 15 big blinds you will need to adjust your strategy again and make decisions about how you approach the endgame based on your opponent type and the depth of stacks.

Against a very weak player and with deeper stacks you should generally apply a small-ball strategy that consists of limping or making small raises and looking to outplay them postflop. With shorter stacks and against tougher opponents you should revert to an ‘all-in or fold’ strategy. If you find yourself up against a very tough player then try to employ a game theory-optimal strategy that they will not be able to counter, involving lots of big bets and bloated preflop pots.

As ever, precisely what approach you take and the frequency with which you do certain things should depend on your opponent. With stacks of exactly 15 big blinds or more, raising to 2.5 big blinds preflop, rather than moving all-in, is obviously superior if your opponent will fold similar ranges of hands to both actions, but less desirable if he will now reraise you with a wider range believing you will fold frequently. In that case you might simply open with a tighter range and call his reraises with a wider one, or revert to a jam-or-fold strategy to deny him any fold equity against you with hands that are playable but cannot stand a reraise. By contrast, limping the button to control the size of the pot is ideal against loose-passive opponents who you will be able to outplay later, but this will not work against aggressive opponents who will raise or move all-in frequently when you limp.

Finish Him!

With stacks of less than 15 big blinds, and especially below ten big blinds, a jam-or-fold strategy is most effective. Small-ball tactics are useless here unless you’re facing a highly exploitable, loose-passive player, or one who is very tight and will fold a wide range of hands to a small raise, making it unnecessary to risk your whole stack to win the blinds.

Against a tough or unknown opponent you should stick to a simple ‘all-in or fold’ strategy that forces them to commit all their chips if they want to play a hand or give up the blinds if they fold. This might be based on your opponent’s tendencies if they are very exploitable (e.g. you might shove more against someone who folds too much) or on a game theory-optimal strategy that will frustrate tougher heads-up opponents who have a good understanding of such strategy themselves.

The latter situation has been addressed by Bill Chen and Jerrod Ankenman in their acclaimed book The Mathematics of Poker. They have calculated tables for game theory-optimal play when heads-up with high blinds. These tables show that for 15 big blinds you can push very wide with even weak hands like 9-8 offsuit or Q-6 suited, as being suited or connected is so useful when you will usually be behind when called. You are also obviously shoving any Ace or pair. Similarly, if your opponent pushes with a wide range you should call with most Aces and pairs, while Broadway hands like K-Q are monsters in this spot since they will rarely be dominated. The suited and/or connected nature of hands is less important when calling all-in.

Remember, make sure you adjust to individual opponents. Against tighter players, calling with a hand like A-2 for 15 big blinds might be bad, and you may wish to pass up very small edges against players over whom you have a large skill advantage until the blinds get very big.