
Defending from the big blind to steal attempts is one of the funnest (yes, that’s an example of language in flux) and most common situations in poker. You both know you’re going to be full of crap a lot of the time, so the leveling war and stand-off begins.
Defending from the Big Blind vs Button Steals
Now obviously we know, and we know that our opponent knows we know, that their opening range on the button is going to be wide. How we play each situation is primarily a matter of several things:
1. How often is our opponent opening? Are they on the very loose side (over 52%), on the tight side (less than 35%), or somewhere in between?
When they are opening wide: In the example to the right, it should expand your flatting and 3-betting ranges. This opponent is opening 58.4% of their range from the button. Assume effective stacks of around 100 BBs, a reasonable flatting range would be something like the following: 77+, A2s+, A9o+, K9s+, KTo+, QTs+, J9s+, QTo+, T9s, JTo. This would be roughly 20% of our total range. Now obviously hands like TT+, AQ+ you’d want to 3-bet a majority of the time. Occasionally, when your opponent is not good post flop, flatting with a lot of these hands can be quite profitable, since they’ll flop second best hands so often.

Also, hands like 77/88, A9o, K9s, T9s, JTo depend on how confident we feel about playing our opponent post flop. If you think if you have a reasonable advantage, flatting with these hands is fine, mixing in some 3-bets. Otherwise look to 3-bet or fold these hands.
Now polarizing some of this range while adding more hands so you can 3-bet some hands that have decent equity when called, and flatting some of the bigger hands like AQo, AJo, KQs, etc., a percentage of the time as well, will keep your opponents defense more off balanced. Of course, most opponents will know that you will defend lighter and 3-bet lighter. So how much, and with what kinds of hands, is important.

Add in some hands to our initial range to create a strong overall defending range: 3-betting hands that won’t play very well if you flat, but that can out flop some of your opponent’s 3-bet calling range. Mix in flatting some of your fairly strong to very strong hands some of the time (exact percentages vary depending upon opponent; baseline percentage would be 20/80 flat to 3-bet). With this range your opponent can’t be extremely confident in your strength when you’re flatting or 3-betting. Most of the uncertainty is going to come with them not knowing which hands you’re polarizing exactly. Some people 3-bet a lot of suited connectors, and offsuited connectors. Some don’t at all, and some people do a percentage of the time.
For the most part I don’t advocate 3-betting suited connectors from the blinds for several reasons. One, there are just better hands to 3-bet, and two, when I am called I’d prefer to have a hand that plays well against my opponent’s 3-bet flatting range. For example, my opponent who opens wide on the button raises to 2.5 BBs, and I have K4s in the big blind. My opponent plays pretty aggressive on later streets, so flatting isn’t a good option. Folding isn’t bad, but if I 3-bet, I can get my opponent to fold X% of the time, and Y% of the time they will flat with hands like 55+, A9o+, JTs+, A5s+, etc., hands that I’m only at a slight disadvantage at pre-flop (around 45/55), and I have initiative. If I flop a king, I have really good showdown value versus their range, and I have semi-bluff potential when I flop or turn flush draws. AK will be 4-bet a majority of the time, so that only leaves KT–KQ, and the combos of those hands are reduced because I have a “blocker” card holding one king.
If you do 3-bet suited and offsuited connectors it’s a bit more difficult to navigate post flop when you do flop a hand. Say you’re in the same situation as the previous example except this time you have 6s7s and you decide to 3-bet. The flop comes and you flop a 6, you continuation bet and your opponent calls. The turn brings no help. You have a pair of 6’s, but you could be quite a bit behind since your opponent’s flatting range is going to have a lot of 77+ hands in it. Your opponent could have floated, and you could have a good equity advantage, but are you check / calling at this point? This situation is still manageable of course, but it’s going to consistently put you in a lot more difficult situations, when there are better situations to really master first.
All of this reasoning is irrelevant if your opponent opens really wide, and folds to a 3-bet a high percentage of the time. Keep in mind, that if you’re using a HUD, an opponent’s fold to 3-bet will be much less when re-defending their open button in most cases. Typically speaking, the time for a situational stat like fold to 3-bet from button defend will take too long to normalize. However, it may provide some clues if it’s an extremely high or low number in a reasonable sample.
If your opponent is opening to 2.5 BBs, and you 3-bet from the big blind to 8.5 BBs, then if your opponent calls 32% of the time or less, it’s neutral EV to +EV. That’s not even considering that when they call you will have equity in your hand, and it’s irrelevant how often they are 4-betting since we’re only looking at folding to 3-bets. To really see if any 3-bet is +EV you’d want to factor in X% of the time your opponent is calling, Y% of the time they are 4-betting. But if X% is already neutral or better, then Y% only becomes relevant when determining exact positive expected value. Again, it will be positive because we already know just based on our opponent’s fold percentage the play is break even or better.
(4 (.68)) – (8.5 (.32)) = 0 EV
When your opponent is calling more than 32% of the time you’ll want to make sure you feel confident playing out of position when you’re 3-betting with a marginal hand. Some opponents rarely fold to 3-bets from the blinds, so you’ll want to avoid 3-betting too liberally with the weaker part of your polarized range. Opponents who fold 50% or less tend to be opponents who are either reasonably good post flop, and don’t mind taking a flop in a re-raised pot, or opponents who are generally stubborn and bad, and just can’t fold. Look for opponents with low fold to 3-bets and high WTSD percents, and you’ll generally be able to sort the stubborn opponents from the reasonably decent opponents.
2. What are stack sizes? As stacks get deeper this will expand your flatting range, and contract your 3-betting range since your opponent will have more incentive to call your 3-bets with a wider range. As stack sizes get narrower, this should have the reverse effect of widening your 3-betting range, and narrowing your flatting range.
3. Is your hand more of a drawing hand or top pair hand? So hands like 78s, JTo, T8s, etc., would be considered more drawing hands versus hands like KJo, ATo, QKs, etc., would be considered more top pair hands. Some hands are both, like KJs, QTs, etc. These hands have good drawing potential, but also good top pair value as well. Top pair only hands usually will make top pair as their best hand most of the time, and these hands are easier to get to showdown versus having a hand like 78s and making top pair. What kind of hand you have will help you decide, based on your stack size, if you should be 3-betting or flatting.