progressBB defense vs BTN open at 30 BB
8-max MTT · ante 12.5 % · Button opens, small blind folds · chip EV
How the BB defends at 30 BB
Facing a Button open to 2 BB (small blind folds) with 30 big blinds, the big blind folds only 8.7% of hands, calls 69%, 3-bets to 7.5 BB with 12% and goes all-in with 9.6%. The big blind already has one blind in the pot and closes the action, so it gets a good price.
Always 3-bet: AA, AKs, AKo, AQs, AJs, A9s, A3o, A2o, KK, KQs, QQ, JJ, TT, 99.
Always all-in: AJo, ATo, A9o, A8o, A5o, 77, 66, 55, 44, 33, 22.
Folded: 94o, 93o, 92o, 83o, 82o, 72o, 62o.
Against other openers at 30 BB the big blind continues with: vs CO 85%, vs HJ 79%, vs LJ 75%, vs UTG+1 72%, vs UTG 72%. The later the opener, the wider its range, and the more the big blind defends.
Closest decisions (the book continues with them only part of the time): Q3o 56%, T2o 44%, 73o 44%, Q2o 40%, T3o 68%. These are the hands worth drilling, because a small change in the opponents or the stack flips them.
What changes around 30 BB
The book continues with 91% of hands here, 91% at 29 BB and 92% at 32 BB. Going from 29 BB to 30 BB, no hand crosses the 50% line; only the frequencies shift.
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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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