Want to check if my understanding of the theory behind 3betting in the small blind and big blind is correct. Any thoughts would be very much appreciated (what's correct, what's not correct and why).


Lets use a BTN open for this discussion.


My thoughts about 3 betting in the SB vs in the BB;

In the SB it is recommended to 3bet your entire continuing range because;

1 you have the chance to not play OOP postflop by getting BB and BTN to fold - instead of a guaranteed position OOP vs BTN and maybe BB, which will be a -EV situation for many hands. Whereas 3betting those hands that are -EV calls might be +EV because 1. You'll win the hand preflop sometimes 2. If BTN does call, you lose less OOP with the stronger range (SB 3bet vs BTN call) in this 3BP, than you would lose with those same hands by calling OOP vs the BTN range (range disadvantage and OOP) in a SRP.

Is this theory correct?


2 As the SB you dont close the action, so even if you call, BB can 3bet a lot forcing you to fold a lot again since you're OOP.
To counter this you'd have to balance SB flatcalls with flatting some very strong hands as well.

If you would balance these flatcalls correctly with strong hands, would the EV of this be lower than just 3betting the entire continuing range?




As the BB though you can both call and 3bet;

1 you get a better price on both a call and a 3bet than SB - so you'll always continue with more hands than SB will.

2 you close the action so you're guaranteed to see the flop with your hand that you call with and realize part of your equity. This works in favor of hands that are too bad to 3bet but +ev calls given the good pot odds.

3 because we call with more of those 'bad' hands in the BB - i think we need to call more good hands as well to prevent our BB calling range from becoming too weak. So lets shift the bottom of the range that we would 3bet from the small blind, to our big blind calling range.

Now our 3bet % is less and the range is more value heavy because we removed the bottom part of the 3bet range. So we need to add some bluffing hands to still incentivize BTN to call some hands, making the range more polar.


So, if we 3bet the same % from the BB as from the SB - the BB range would be more polarized than the SB, so we call some hands in the BB that we would 3bet from the SB, and we 3bet some hands from the BB that we would fold in the SB?


Another question;

We get a good price on a call in the BB - but is this moreso a reason to call with a wider range than it would be to 3bet a wider range? Considering we get the same 1bb cheaper price on the call, as we do on the 3bet?

Depends on rake ???????
anyway that sounds more exploitive then balanced. Just about any solved range out there will have some flats

Your understanding of the incentives seems sound. But there’s a lot of nuance here, and tbh it’s impossible to answer all of your questions honestly without writing a massive wall of text. Try narrowing your questions down a bit. I'll focus on the SB aspect of your question.

Some food for thought:

• How wide you can 3bet is mostly a function of the aggressor's range rather than their sizing.
• How wide you can call is mostly a function of pricing and equity realization. Facing a 2.5bb open, any SB hand that recoups at least 2bb can call (although a raise might be more profitable).
• The idea that SB never flats is just an oversimplification. SB almost always has a flatting range, although in high-rake cash games it's so slim that many simplify to a 3bet or fold strategy.
• You could change your range to flat more in SB, but that requires more protection, so you’d need to sacrifice the EV of a 3bet with some nutted hands that now call.

Analyzing GTO ranges:
You can view these for free on GTO Wizard if you make an account.

Here's a SB chart vs BTN open (2.5bb) from GTO Wizard with a NL500 rake structure. There's not much calling, so this can be simplified to a 3bet or fold strategy.



Here's how SB reacts to a UTG 2bb open (NL500). There are a lot more calls.



The difference here is that

1) UTG's tighter range prevents BB from squeezing too frequently, so your calling range sees a flop more often.
2) UTG opened to a smaller size (2bb instead of 2.5bb), so SB has better pricing on a call.

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Now here's a SB vs BTN 2.3bb open for 8max MTT (100bb). Way more calling, and wider in general.



The difference here is that:

1) BTN opened smaller, giving SB a better price on a call.
2) BTN opens 10% wider (due to ante), so SB can continue wider.
3) There's no rake.

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As you can see it's not that straightforward. Even the bullet points I gave at the top of the post are oversimplified and missing information. But that's the nature of trying to describe a game this complex in a forum post.

Thank you!

More complex than I thought originally