Introduction to Heads-up

Introduction

In this article we will cover...

• The differences to 6max
• Ranges & Lines & Structure
  
• Advanced levels of play
  

There are many players who consider Fixed Limit Heads-up to be the highest form of poker. No where else will you find such wide ranges, looser call-downs or more bluffs.

For the untrained eye, FL HU may seem like a game of random calls and raises. The truth, however, is that it is a complex game that doesn't only revolve around bluffing and re-bluffing. Just like the other variations, it remains a game of poker with its own unique characteristics. To play successfully you will have to master these new aspects and adapt your game accordingly.

FL HU is a dynamic game. You will have to learn to spot your opponent's weak spots and exploit them to gain an advantage. This is difficult for many players who are new to heads-up games, since they often have difficulty getting away from their old habits of multi-tabling, using charts and making standard moves.

Low Limit ring games, even short-handed ring games, can be played profitably by carefully choosing your starting hands and playing solid poker after the flop. Players who multi-table usually make their reads based on an opponent's stats rather than his play.

Knowing your opponent's stats alone won't get you far in heads-up; what counts is giving the game your undivided attention. Study your opponent's play, analyze his actions and adapt according to his playing.

If you're up against a poor player you can win by letting him play his normal TAG-ABC style, as he won't be able to use it to his advantage. If you find yourself up against a better player, however, you will get into trouble if you can't adjust your game.

This article will introduce to the general concepts you will need to understand to play heads-up successfully.

What do you need to pay attention to before the flop?

Since you are always in a blind position before the flop you can play more hands than in a ring game. A VP$IP of 60-100% can be played profitably in heads-up, whereas you would need a VP$IP of app. 25% in a ring game with 6 seats. Playing with less than 60% can even be OK in heads-up. The following factors should influence your decision regarding the number of hands you play:

In most games you will find a 1/2 blind structure, meaning the Big Blind is two times the Small Blind. Depending on the platform and limit, though, you can find other structures, such as: 1/3 in 3/6$ games, 2/3 in 15/30$ games, and 2/5 in 5/10$ games at PartyPoker.

If the small blind is disproportionally smaller than the big blind you should be tight with open raises. In this situation the investment is expensive and you will need more equity/fold equity than usual in order to play profitably.

If you're the big blind in a 1/3 or 2/5 structured game you will also need more equity to defend or make a 3-bet, since the Small Blind will usually only raise with a strong hand. With this structure your VPIP and PFR usually drop.

The opposite is the case when the Small Blind is disproportionally large compared to the Big Blind. You can be loose with open raises and be loose defending, as long as your opponent also adjusts his game and loosens up his open raises. If he doesn't, however, you will have to be careful not to end up play too loosely. You can gain an advantage against an opponent who plays 1/3 structured games like 1/2 games by defending your big blind as if it were a 1/2 game and adjusting your open raising range in the small blind.

Depending on where you play the button may rest with the Small Blind (PokerStars, Full Tilt Poker) or the big blind. This will have an impact on your play.

Although position doesn't play as important a role in Fixed Limit as in Pot Limit Omaha or Hold'em, having position after the flop brings an advantage. This should influence your readiness to get involved in a pot. You can open-raise or defend more loosely when you know you will have position after the flop.

If, for example, you are playing heads-up at Pokerstars (SB = BU) you can be loose with your open-raises (depending on the blind structure and opponent you can open-raise up to 100% of the time), but should be more cautious when defending. If, however, you notice your opponent adapts his play and starts raising from the SB regularly you will have to adjust your defense and call more often from the BB.

At other sites where BB = BU you should be tighter with open-raises, while defending more hands from the BB. Once again: If you notice your opponent adjusting his play you will have to adjust yours, too, which means defending less hands against open-raises.

Your standard play should depend heavily on the actions of your opponent. It's important to get a feel for how he plays before and after the flop.

Your range for open-raising depends on how often your opponent folds his hand before the flop. Many players defend up to 100% of their hands in a heads-up match. If you're up against such an opponent, you will have to be tighter with your raises, as you won't have any fold equity. You can also muck trash hands regardless of what position you will have after the flop.

If, on the other hand, he tends to fold before the flop, you should raise more often. If your opponent folds his BB often (25% of the time against a raise) you can open-raise 100% of the time against him, as you can be sure to regularly win his BB.

Your defense should depend on your opponent's play, as well. The more he raises the looser you can defend.

When making your pre-flop decisions you should take your opponent's post-flop play into consideration. If he often folds against continuation bets you can raise more loosely. If, however, he never folds on the flop, plays aggressively and looks to see the showdown you will have to choose your hands to raise with more selectively.

You should also adapt the range of hands you defend with according to your opponent's play. If you are able to bluff your opponent out of the pot after the flop you can defend more loosely, up to 100% of the time if he is loose with his open-raises. The actual strength of your hand isn't as important in such a situation, as you will be able to win many pots without having to improve your hand.

Good players generally have a raise/defend statistic as follows:

• SB = Button: SB raises 70%-80%, BB calls 90%-100%
• BB = Button: SB raises 60%-70%, BB calls 80%-90%

Here the percentages refer to strength of your starting hand. You can use the Equilator to determine the percentage strength of a starting hand. You may find some variation, as the ranking is based on the EQ and not the playability of a hand. This explains why a player might fold T2o, which is in the top 80%, but call with 54o, which isn't.

Although it may seem paradox, you will defend more often out of position than in position. The reason - when the SB = BU, the SB will open-raise more loosely. If, however, you notice the SB folding more than 20% of his hands, you will have to defend more tightly (80-90%), as an open-raise will indicate a strong hand.

Be careful not to open-raise too loosely when the BB = BU. Some players tend to open-raise out of position 100% of the time in an attempt to win the blind war. Theoretically this is a leak however, since your opponent could defend with the same range (100%) and have the advantage of position.

What should you pay attention to after the flop?

Even after a continuation bet on the flop, you will often be up against a wide range (up to 100%) of possible hands. This is due to the loose standards in preflop open-raising and defending. This is one of the elementary differences between heads-up and ring games and requires short-handed players to greatly adapt their play.

Most beginners in heads-up play make the typical mistake of folding too often, because they underestimate the equity of their hand. The value of a marginal hand is much higher in heads-up play; an ace or king high will often place you far ahead of your opponent.

UTG: TAG (UTG Range = ORC)

Preflop: Hero is BB with QJ
UTG raises, 4 folds, Hero calls.

Flop:(4 SB) K, 2, 3
Hero checks, SB bets, Hero's Equity: 19%

In a 6max game you are usually hopelessly behind after the flop against an UTG raiser. You are better than JTs or QTs, but basically drawing dead against any other hand. Your equity is only at 19%.

Usually you would check/fold. However, since you will almost never be ahead, you have fold equity against better hands. An opponent's ace high can be made to fold after the flop, or after the turn at the latest. This makes check-raising possible in this situation.

UTG: TAG (HU-Opening-Range: 85%)

Preflop: Hero is BB with QJ
SB raises, Hero calls.

Flop:(4 SB) K, 2, 3
Hero checks, SB bets, Hero's Equity: 48% !

The ratios are completely different in heads-up! Your Q high is often the best hand on this board. You are rarely the underdog, if at all.

Whereas check/folding would clearly be correct in a ring game, it is not an option you should consider in heads-up. You should definitely call on the flop and the turn, since the range of your opponent's hand doesn't change greatly after a second continuation bet.

A check-raise as a bluff will usually not be successful here, as your opponent is unlikely to fold a good hand knowing that you, too, have a very wide range. Furthermore, a check-raise in heads-up does not show nearly as much strength as a check-raise against an UTG raiser, who will usually have a strong hand. Usually your opponent won't have a better hand and you are opening the door for him to re-bluff against you.

In general you will have to call much more loosely in heads-up than in other games, because your opponent will rarely have a good hand. This means that you don't need a pair or an ace to have enough equity to continue playing. This counts for high card hands and small pairs with high cards on the board.

It is very important to adapt to your opponent however. Many opponents on smaller limits play very tight and straightforward, which means you might need to fold more often.

It is wrong to assume that heads-up play should revolve around bluffing and re-bluffing. You will, however, lose a lot of value against an opponent by not incorporating bluffs into your game. The reason is simple: usually your opponent will not have hit anything.

Because he will be playing such a wide range of hands he will inevitably often not have hit and will be willing to fold if you show aggression. Your wide range of playable hands also means you can represent at least a pair on nearly any board.

If you only raise with strong hands your opponent won't give you any value when you do hit. If you don't find a good balance of value plays, bluffs, semi-bluffs etc. you will make it easy for a good opponent to optimally adjust his play to yours.

Preflop: Hero is BB with 63
SB raises, Hero calls.

Flop:(4 SB) K, 8, 4
Hero checks, SB bets, Hero raises

It is safe to assume that you can make your opponent fold any hand queen high or worse, though not a small pair or a draw
(Q9s+,Q7s-Q5s,Q3s-Q2s,J9s+,J7s-J5s,J3s-J2s,T9s,T7s-T5s,T3s-T2s,97s-95s,93s-92s,85s+,83s-82s,73s-72s,63s-62s,53s-52s,32s,QTo-Q9o,Q7o-Q5o,Q3o-Q2o,J9o+,J7o-J5o,J3o-J2o,T9o,T7o-T5o,T3o,97o-95o).

This makes up 36% of his range. It is therefore profitable to bluff, as you will be investing 2 Bets for the chance to win 7 bets (28.5%). For more you can read the following article:  Pure Bluff.

As you can see, it is profitable to bluff against a tight opponent on many boards without taking other aspects into consideration. If your opponent calls or even re-bluffs with hands like QJ or a backdoor draw you will have to adjust and won't be able to bluff as often as you would against a tighter opponent.

Bluffs bring more overall value than direct fold equity. They allow you to get more value from your made hands, because your opponent will be less likely to believe you when you do have a strong made hand. By adjusting your play with respect to value bets you can gain an advantage.

(Depending on your opponent, of course) You should generally make value bets in a heads-up match that you wouldn't be able to make in a ring game. Depending on the situation you can make a value bet with an ace or a king high, and you can regularly make value bets with pairs.

Preflop: Hero is BB with 43
SB raises, Hero calls.

Flop:(4 SB) T, 8, 4
Hero checks, SB bets, Hero raises, SB calls.

Turn:(4.75 BB) 2
Hero bets, BU calls.

River:(6.75 BB) K
Hero value bets

It is possible for an opponent to passively call you down with a hand in the range of 33-77, but it is more likely that he will only have an ace high. He will then most likely call on the river, because no draw will have been made. A value bet will be even more effective if you continued to bet on the river on a similar board with nothing in an previous hand.

The flip side of the coin is that opponents will also be more likely to bluff or make a value bet with a marginal hand. As a result you should be looser when calling down your opponent.

This comes into play in two different situations: Either you are facing a raise (your play will depend heavily on your opponent and the situation at hand) or you are facing a continuation bet with Q, K or A high and make a call based on your equity. Remember, due to the wide range of hands your opponent might have you usually will have enough equity to call a bet on the flop. Depending on how often your opponent makes a second continuation bet you may call the turn. You can read more about equity after the turn in the platinum article Playing the Turn OOP Without Initiative and with Showdown value. You will, of course, have to take your opponent's range into consideration when making this decision.

Balancing doesn't play a large role in low limit games with a wide range of players, of which many are weak. Your opponents probably won't pay much attention to the way you play a type of hand and even if they do, they probably won't be able to get an edge on you.

The opposite is the case in heads-up. Since you will be playing a lot of hands against the same opponent you will have to balance your lines. If you don't your opponent will probably get good reads on you and be able to exploit you. You can find more general information on balancing and adaptation in the following article found in the platinum section: Intro to Heads-up After the Flop

We have already mentioned an important tool for balancing your play, namely bluffing. If you always play a certain line with a certain type of hand, a good opponent  will take notes and soon know what kind of hand you have in any given situation. He will know when to re-bluff and when to make a difficult, but correct, fold.

A good opponent will learn to recognize the situation and adapt. He might start 3-betting the flop to protect made hands, or do so as a bluff or semi-bluff. He knows if you are on a draw that you will fold before reaching the showdown. He will also be able make tough folds on the turn (A high or a small pair), preventing you from getting paid off with strong hands.

Having stressed the importance of balancing your play and playing certain lines with different types of hands, it follows that it is just as important to identify your opponent's weak spots and to exploit them.

You will have to adapt and adjust your game. Try to identify common mistakes your opponent makes, and specific lines he follows.

There are a number of general tendencies and weak spots an opponent might have, which you will want to identify and exploit.

This won't take you very far against solid players (many TAGs, for example), however, since good players rarely make elementary mistakes. If you're up against a good player you will have to carefully analyze his play in order to find a weak spot, such as lines he does not balance well enough, in order to take advantage of it.

The trick is to get away from your standard play to maximize your EV. Take a look at a few examples of how you can adjust your moves to exploit an opponent after careful observation.

• Observation: Your opponent always makes a blind continuation bet on the turn.
• Adjustment: With made hands and draws you call on the flop and raise on the turn!

Preflop: Hero is BB with T2
SB raises, Hero calls.

Flop:(4 SB) 2, 7, 4
SB bets, Hero calls.

Turn:(3 BB) 3
SB bets, Hero raises

Preflop: Hero is BB with K6
SB raises, Hero calls.

Flop:(4 SB) 6, 8, 3
Hero checks, SB bets, Hero calls.

Turn:(3 BB) 4
Hero checks, SB bets, Hero raises

• Observation: Your opponent check/folds the turn when he has initiative.
• Adjustment: Call (bluff) the flop and bet if he checks the turn card!

Preflop: Hero is BB with 97
SB raises, Hero calls.

Flop:(4 SB) 6, Q, 3
SB bets, Hero calls.

Turn:(3 BB) 4
SB checks, Hero bets

• Observation: Your opponent check/calls the turn with initiative and SD value.
• Adjustment:
  Make loose calls on the flop and check with hands that are probably behind. Raise with made hands (and bluffs) after the flop.

Preflop: Hero is BB with 78
SB raises, Hero calls.

Flop:(4 SB) 2, J, 6
SB bets, Hero calls.

Turn:(3 BB) 4
SB checks, Hero checks

Preflop: Hero is BB with Q8
SB raises, Hero calls.

Flop:(4 SB) 6, Q, 3
SB bets, Hero raises

• Observation: Your opponent plays weak hands and draws aggressively on the flop and waits for the turn to raise with a strong hand.
• Adjustment: Re-raise after the flop with medium strength hands and make tough folds on the turn.

Preflop: Hero is BB with K8
SB raises, Hero calls.

Flop:(4 SB) 8, Q, 6
Hero checks, SB bets, Hero raises, SB 3-bets, Hero caps, SB calls.

Turn:(6 BB) 3
Hero bets, SB calls.

Turn:(8 BB) 7
Hero bets, SB calls.

Preflop: Hero is SB with 98
Hero raises, BB calls.

Flop:(4 SB) 8, Q, 6
Hero bets, BB raises, Hero 3-bets, BB calls.

Turn:(5 BB) 3
Hero bets, BB calls.

Turn:(7 BB) 7
Hero bets, BB calls.

Preflop: Hero is BB with 66
SB raises, Hero calls.

Flop:(4 SB) 7, J, 5
Hero checks, SB bets, Hero raises, SB calls.

Turn:(4 BB) 2
Hero bets, SB raises, Hero folds.

• Observation: Your opponent often folds before the flop.
• Adjustment: Open-raise any 2!

• Observation: Your opponent quickly folds after the flop and doesn't re-bluff.
• Adjustment: Attack whenever and wherever possible!

...

Your opponent may have any number of leaks that you can exploit. Consider where you might find a weak spot and make a plan to take advantage of of it as soon as the opportunity arises!

It is, of course, possible that your opponent will recognize these tendencies and adjust by playing counter-lines. Once he does it's time for you to re-adjust your play.

FL HU is a dynamic game. You will constantly be receiving new information and re-thinking what you "know" about your opponent. Your image, as well as your opponent's image, will constantly be changing. A heads-up game against a good opponent is kind of like a professional game of rock-paper-scissors (RPS).

You have to get into your opponent's head - ask yourself what he is thinking, ask yourself what he thinks you are thinking. He will be doing the same. If he gets one step ahead of you in his thinking, you will lose. If you get two steps ahead of him in your thinking, you will lose. Success comes by always being exactly one step ahead of your opponent.

The comparison to RPS is actually quite fitting (many good FL HU players are also good RPS players). Here's an example: 

Round one in RPS: you take paper, your opponent the rock. What do you consider before playing the second round? You have to carefully contemplate your opponent's level of thinking, which will depend on his history and skill.

Is he thinking that you think he will choose the same thing twice, and therefore that you will choose paper again, which will lead him to choose scissors? Or is he thinking, you don't think that he will think that you will make the same choice, which leads you to once again choose paper?

In RPS it is easy to play unpredictably and prevent your opponent from being able to exploit your play. Just make your choice at random every time. This would make your EV 0 against any opponent. With this strategy you will never have +EV, but you will never have -EV, either.

Of course it is somewhat more complicated in poker than RPS. It's much more difficult to find the optimal strategy, because you won't have the same EV for every action. Furthermore, your goal is to carefully exploit your opponent and not to play with +/-0 EV.

As in RPS, you have to get inside your oponnent's head. The difference, however, is that your decisions should not come at random, but be strategically based.

First hand in HU: You call the flop and raise on the turn with a strong, made hand. Your opponent calls you down with A high. What kind of hand will you need to raise in the next similar situation on the turn? Would you bluff, or only raise with a strong, made hand? This depends on what level you think your opponent is thinking.

Level 0: Your opponent isn't thinking at all and is only interested in the board and his own cards.

Level 1: Your opponent doesn't expect you to balance your lines. He thinks you will always play strong, made hands by calling on the flop and raising after the turn. In the next similar situation you should bluff and raise after the turn.

Level 2: Your opponent is thinking one step ahead and believes you could easily play the same line as a bluff. If this is how your opponent is thinking you should only raise with a made hand.

Level 3: Your opponent is thinking yet another step ahead and believes you might purposefully play the same line with the same hand, because he thinks that you are thinking ahead, as well. In this case you should bluff and make a raise.

Level 4: Your opponent thinks, that you are thinking what he is thinking, etc. Continue by raising a made hand.

You will only make the right decision by correctly putting your opponent on the level on which he is, in fact,  thinking. Then you just have to think one step ahead to be successful. This sounds complicated, and when you put it into practice you will realize that it is even more complicated than it sounds, as you will rarely have the exact same situation repeating itself and you have to take many additional aspects into consideration when making your decision.

Of course, there is no need to ponder such things when playing against weak opponents, as they will only be paying attention to the board and their own cards.

When you start playing FL HU in higher limits, and especially when you play against the same opponent repeatedly, you will find the game getting more and more complex, as the information you receive and the history of play continue to grow. It becomes increasingly important to get into your opponent's head and exploit his weak spots.

Once these metagame aspects come into play you will no longer be able to play each hand as an individual hand and make an analysis of the situation without taking the game flow and history into consideration.

Your image will play a significant role. A single decision may be in and of itself -EV, however, the information you receive and the extra value you will have for future hands can ultimately result in it being +EV. .

This doesn't mean you should cap the first hand with trash in order to make your opponent think you are a maniac. You should, however, always be aware of the image you are creating with your play and be able to make adjustments in future hands.

The rake in $5/$10 and under limits is considerable. You can only play profitably if you can gain an edge on your opponent. Always keep this in mind. Be careful not to spend too much time trying to identify weak spots in your opponent's play. If you haven't found a leak after 50-100 hands there is no shame in avoiding that opponent.

Even if you have a theoretical edge of 0.5BB/100 there would be two losers with a rake of 2BB/100: you and your opponent. After a long session both of you will be down and the casino will have taken a nice rake.

Be careful if your opponent makes confusing moves. Just because you can't understand what he has just done doesn't necessarily mean he has made a mistake. If you have no idea how to exploit such play it's quite possible that you are the one being exploited. You should soon have an impression of your opponent. If you can't find any weak spots after a short time you should simply look for another victim.

Conclusion

Playing pure heads-up is complicated and requires you to adapt. Before the flop you have to pay attention to the blind structure and the button, in order to choose the right strategy. You have to get away from standard play and react to your opponent in order to get the maximum EV from your hands.

After the flop you have to identify your opponent's weak spots. Once you have found them adapt your play and take advantage of your opponent.

This article has taught you the basics for reading your opponent and adjusting your game. If you can't find a weak spot to exploit you have to have the discipline to leave the table, as there is no point in paying the high rake.

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Related articles: Pure Bluffs Intro to Heads-up After the Flop Playing the Turn OOP without Initiative and with Showdown Value Discussion Forum: Discuss this Article in the Form