progressBB defense vs CO open at 80 BB
8-max MTT · ante 12.5 % · Cutoff opens, small blind folds · chip EV
How the BB defends at 80 BB
Facing a Cutoff open to 2.2 BB (small blind folds) with 80 big blinds, the big blind folds only 27% of hands, calls 60%, 3-bets to 11 BB with 13% and goes all-in with 0.2%. 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, AQo, AJs, AJo, ATs, KK, KQs, QQ, JJ, TT, 99 and 1 more.
Folded: K2o, Q6o, Q5o, Q4o, Q3o, Q2o, J4o, J3o, J2o, T5o, T4o, T3o and 13 more.
Against other openers at 80 BB the big blind continues with: vs BTN 71%, vs HJ 73%, vs LJ 70%, vs UTG+1 68%, vs UTG 67%. 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): K4o 48%, Q7o 46%, T6o 54%, J6o 56%, 42o 58%, 32o 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 80 BB
The book continues with 73% of hands here, 73% at 70 BB and 74% at 100 BB. These leave it: K4o.
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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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