progressBB defense vs BTN open at 8 BB
8-max MTT · ante 12.5 % · Button opens, small blind folds · chip EV
How the BB defends at 8 BB
Facing a Button open to 2 BB (small blind folds) with 8 big blinds, the big blind folds only 27% of hands, calls 43%, 3-bets to 4 BB with 5.1% and goes all-in with 25%. The big blind already has one blind in the pot and closes the action, so it gets a good price.
Always 3-bet: 99, 88.
Always all-in: AA, AKs, AKo, AQs, AQo, AJs, AJo, ATs, ATo, A9s, A9o, A8o, A3o, KK, KQs, KQo and 7 more.
Folded: Q8o, Q7o, Q6o, Q5o, Q4o, Q3o, Q2o, J6o, J5o, J4o, J3o, J2o and 12 more.
Against other openers at 8 BB the big blind continues with: vs CO 73%, vs HJ 75%, vs LJ 74%, vs UTG+1 73%, vs UTG 71%. The defence does not simply grow with the position of the opener here; the exact chart for each opener matters.
Closest decisions (the book continues with them only part of the time): 52o 50%, T6o 44%, 63o 60%, 74o 62%, 32o 62%, J8o 64%, plus 4 more mixed hands. These are the hands worth drilling, because a small change in the opponents or the stack flips them.
What changes around 8 BB
The book continues with 73% of hands here, 72% at 9 BB.
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Numbers come from the progressGTO solution book (v14, chip EV, 8-max, ante 12.5 %): our own equilibrium computation with a modelled postflop. It is an approximation, not an exact solution, and it keeps improving. Hover or tap a hand to see its exact frequencies.
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