OTB #041: How to Exploit the Nitty Big Blind

When you sign up for my signature programme, Train & Play Like The Pros, one of the first things we'll look at is whether you're defending the big blind enough versus late position opens.

Facing a Button open, on average, you should fold 23.3%, call 58.5% and 3-bet 18.1%. Most players that start the programme are folding too much and not calling or 3-betting enough.

When you understand this, you realise that a lot of the population are doing the same.

Today I want to show you two exploits you can make from the Button the next time you're up against a Big Blind who, maybe like you, is folding too much and not 3-betting enough.

Let's dive in...

It all starts with the ranges

At 30bb effective in solver land, you can open this range from the Button when folded to:

Here's what the Big Blind's strategy should look like facing a Button min raise at 30bb:

You might look at this range and know that the players in your games aren't 3-betting this aggressively, perhaps preferring to just 3-bet hands for value (the hands in pink at the top of the range) and missing many of the bluffs (the hands in pink at the bottom of the range).

You might also believe that they're not calling anywhere near as many hands as this and they only jam pairs and the big offsuit Ax hands.

That means their adjusted range might look something like this:

Note: You could take this further and believe that the nitty Big Blind isn't jamming all those pairs either at 30bb, but I had to draw the line somewhere. The main focus is that their 3-betting and 3-bet jamming range is stronger than it should be in solver land, and they're folding too much preflop too.

Think like a dentist...

When the Big Blind folds too much and doesn't 3-bet enough, you can open much wider.

You go from opening 49.5% at equilibrium to 58.2%. You can now open all the offsuit 7x hands and more suited hands as well:

Because the Big Blind folds too much, many hands in this range now make EV just by stealing the blinds.

Now imagine the Small Blind folds too much and doesn't 3-bet enough as well and you could easily get to open ~70% of hands here instead.

Here's the clincher...

So the obvious exploit is just to open a lot more hands. But one overlooked exploit is how to adjust when the nitty Big Blind does 3-bet or 3-bet jam.

When the BB 3-bets to 7.5bb, here's a comparison of what to do at equilibrium (left) and the adjusted strategy (right):

You go from continuing 52.7% of the time to continuing just 12.4% of the time, which means you're folding a huge chunk of your opening range.

When the BB jams, here's a comparison of what to do at equilibrium (left) and the adjusted strategy (right):

You have to start folding some Ax hands, together with almost all the suited broadways and pockets 4s as well.

Today's action tip

You can use HUD stats, reads or population analysis to identify if a Big Blind is folding too much to Button opens and/or not 3-betting enough too. In PokerTracker 4 you do this by creating an "All Players Report" and adding "Fold vs BTN Open", "Call vs BTN Open" and "3-bet vs BTN open" as the key stats.

Using this data, run your own toy game sims to show you the exploits.

Of course the solver is still assuming that both of you are going to play perfectly postflop so there's probably some wiggle room, but this is a really good way to start your journey to exploiting the leaks you see in your opponents' games.

That's it for this week.

See you next time.