Now we examine the different aspects of defending the big blind post flop. To keep the analysis consistent, we’ll assume that we will be first to act after the flop (the small blind folded) and that the scenario occurs near the bubble of the tournament. On the surface, this scenario looks a lot like standard post flop play, but there are a few small differences.
1. You are likely not holding a strong starting hand
2. You are facing an aggressor but have no real idea what they are holding.
3. You will be first to act, which actually acts as a positional advantage at this stage of the tournament.
4. The pre-flop call coupled with any post flop bet will be substantial given the stage of the tournament.
Given those things, lets take a look at when you should be betting. I’m going to assume that you will continue with a half pot sized bet. Let’s look at all of the situations you will encounter.
1. You Hit Anything (approximately 37% of the time)
This is a no brainer. You should be betting here with anything. According to the Wilson Software site, a pair will be the best hand 90% of the time on the flop, given that the flop is unpaired (if the flop is paired, you both have a pair). This site also gives us the statistic that 81% of the time, the single pair holds up to win. Therefore, you are favored to win 73% (.9*.81) of the time should your opponent remain in the hand.
If you flop two pair or greater, you should seriously consider slow playing the hand or attempting a check raise if there aren’t any obvious draws out there.
If you encounter resistance by being called or raised, you really need to think about folding the hand or checking down unless you have trips or better. Don’t worry about appearing weak. Oftentimes, this is how people are eliminated in the bubble stages, and you don’t really want to blow the sit and go on a hand where you sole purpose was to defend the blind. You can afford to wait for a situation where you can be the aggressor or have cards that you feel can hold up.
2. You Hit a Draw
If you hit a straight or flush draw, you should bet. Here are the likely situations.
A. 63% of the time your opponent has nothing
It’s a pretty good assumption that your opponent will fold with nothing if you make a bet. Yes, I know there are lunatics who will reraise thinking you are weak or on a draw, but those players have normally been eliminated by the middle/bubble stages.
B. 37% of the time you opponent has something.
I. A pair but not top pair
Knowing what we know about pairs winning 73% of the time, calling with any pair (or even raising) wouldn’t be a bad idea for your opponent. They do, however, face a dilemma if they do. If they hold second pair that is a King or Queen, they are calling against a hand that you likely have. You called a raise pre-flop, and now lead out when an Ace or King flops. A caller here is begging to go broke especially if they see the flush and/or straight draw out there. If they hold second pair lower than that, they not only face the straight and/or flush draw but the possibility that more over cards could come. In addition, they will be the underdog if one of you cards is higher than theirs and you have the draw. Unless you have been playing extremely loosely, any rational player will fold with second pair in this situation.
If they have third pair, this is an automatic fold for most players.
II. Top Pair or higher
In this situation, your opponent will likely call or raise you. If they call you, you will get to see fourth street, and you will need to play the situation carefully. I don’t suggest you slow play if you hit your draw on fourth street. It’s unlikely that any a rational opponent will commit any more chips with the draw on the board, and you really don’t want your opponent to know what you are holding. The reason for this is that you were trying to deter him from stealing, and you would like for them to have to guess if you made your hand or not.
If they raise you, you probably need to fold and wait on an opportunity to commit your chips as the aggressor and favorite. You can look at the pot odds, but most of the times they are secondary to survival.
While you can’t calculate an exact number as it depends on the hands (AT has a much higher probability of being top pair than 56s), situation one, your opponent hitting less than top pair, is much more likely than your opponent hitting top pair or better. A reasonable estimate is that your opponent will fold to a bet 80% of the time when you have a straight and/or flush draw. This will make betting extremely profitable, and this doesn’t even count on the times you hit your draw.
3. You Hit Nothing
If you hit nothing, you will have a decision to make. For those of you interested in statistics, the probability that one of you hit the flop and the other didn't is 22.9%. A mind boggling 41.5% of the time, you both missed the flop and 12.7% of the time both of you will hit the flop. That means that only 22.9% of the time you opponent is holding a pair, when you have nothing.
Against a tight opponent, you should go ahead and bet half the pot with anything. It will be a profitable play in the long run. If you have applied the criteria for selecting which hand to defend with, you are not in against a rock and likely up against a semi-strong to average hand, so the texture of the flop doesn’t matter.
Against a loose opponent, you will want to be a little more selective, because they are more susceptible to call, chase, or reraise. Against this opponent, you should only bet when a flop hits that it is probable that you hit. If your opponent knows that you are selective about the hands you play, you will be facing a lot of reraises on blank flops. Because you will be betting into decent flops, you will run into hands occasionally, so you will need to slow down immediately if you encounter resistance.
In closing, the data looks pretty convincing that you should be betting after you have decided to defend the blinds in just about every situation. While this seems aggressive, it is effective and will help you in deterring opponents from attempting to steal your blinds even more.
