3 Tips for Defending Your Blinds

When you first learn to play poker, you are taught not to play marginal holdings out of position, but in short-handed formats where the blinds are attacked with very wide ranges, playing marginal hands out of position is exactly what you need to do. Let’s start with some simple maths.

Understand the EV of Folding

What you must remember is that, from the point of view of the full hand, folding your big blind costs you 1BB. Its EV from this perspective is -1BB. Many of the hands that you need to defend in the big blind will also cost you money when you play the same spot over thousands of trials, but they may lose you less than 1BB. Let’s take an example:

Imagine that you are dealt J♠7♠ and face a 2.5BB raise from an aggressive regular on the BU. Folding will cost 1BB. In order for calling to be better than this, you will need to get back your 1.5BB investment and a little bit extra on average. This could lead to you recouping a little bit of that big blind you posted. Perhaps your EV by calling will only be -0.8BB instead of -1BB.

After you make this call, the pot will be 5.5BB (2.5BB from each player plus the dead SB). If you can get back more than 1.5BB on average then you have made a profitable pre-flop call as you have regained your investment plus some of your BB that you would have surrendered in its entirety by folding pre-flop. Even if your pre-flop call is still a losing situation in the long-term, folding might have cost you more.

It is crucial to frame blind defense as a matter of loss mitigation. Since the 1BB is already posted, it no longer belongs to you,it belongs to the pot. Therefore, any call or 3-bet that results in an average loss smaller than -1BB is preferable to folding.

The question now becomes: how much of this pot are you entitled to on average based on your hand vs. Villain’s range, your position, and the relative skill levels of each player?

Your hand is clearly not a powerhouse, but against a 45% BU opening range, which is close to what you might expect from an aggressive opponent, you have a respectable 42% equity. Of course, you do not expect to realise all of this due to your poor position, but you would expect to get back at least around a third of this pot on average. To break even on the pre-flop call, you only need to recoup 1.5BB which is 27% of the pot. You can make a good call here that will lose you less money than folding would.

3-Bet to Deny Villain’s Equity

While it is fine to defend your big blind by calling small raises, it is also important to throw some 3-betting into the mix. The idea here is that an in-position raiser will do quite well if he is always allowed to see the flop. He acts last on every street and can control the pot-size effectively. Also note that 60% of the five community cards appear on the flop. This means that a button raiser will realise 60% of his equity when called by the BB. In order to bring that 60% down to 0% you will need to charge the late position raiser from time to time, forcing him to make speculative calls with his weaker holding or surrender the whole pot.

What hands should you 3-bet with from the BB against a steal? A good starting point is to always 3-bet a late position raiser with hands like [TT+ AQo+ KQs+ AJs+]. These hands are very far ahead of Villain’s opening range and will even be in great shape if he calls the 3-bet. It is very much in your interests to force Villain to pay more to see flops when you are holding a hand that is such a clear favourite. Do not let the in-position player see three or four cards for free when he has such a wide range and you have such a powerful hand.

On top of this, you should also look to mix in 3-bets with some hands that are in okay shape when called and would very much like to end the pot now, denying Villain any way of realising equity when he holds a weak hand. Hands like [77-99 ATo-AJo KJo-KQo+ A2s-ATs K9s-KJs+ QTs+ J9s+ T8s+ 98s 87s 76s] can either be used as a 3-bet or a call in the BB facing a BU raise. Although many of these hands are not ahead when Villain calls your 3-bet, they will make up for marginal equity by winning the pot uncontested pre-flop enough of the time.

When 3-betting from the blinds, remember that you will be playing the rest of the hand out of position. To compensate for this disadvantage, use larger sizing (typically around 3.5x, sometimes larger against loose opponents) to maximize fold equity and make it mathematically difficult for the opener to continue with speculative holdings.

3-bet often and aggressively to dissuade players from thinking that they can steal your blinds without repercussions.

Pay Attention to Open Sizing.

There is a great deal of difference between facing a 2BB open and a 3BB open. Hands such as: [85s, 98o and A5o] are mandatory defends to the smaller size and mandatory folds to the larger one. Your pot odds are your measure of how well your hand needs to perform in order to call; listen to them.

In modern games, many players have moved toward a min-raise (2BB) strategy from the button. Against this sizing, your pot odds are so favourable that optimal strategy requires you to defend an extremely wide range of hands, including most connected hands and suited hands, simply to prevent being exploited by frequent steals.

Against larger open-raises, calling becomes a worse idea as the investment becomes too large in relation to the pot size. Where players are choosing to open with very large sizes such as 3.5BB or 4BB, look to 3-bet most of the hands that you are playing and make your opponent justify why he is investing so much money with a wide range. Beware that there can be a very large swing in EV between calling a small raise and calling a big one.

Conclusion

Transitioning from a solid beginner to an intermediate player is all about understanding when to leave the safety net of ‘tight is right.’ Blind defence in late position battles is one of the first areas in which you should look to do this.