Big Blind Defense vs Button: A Good Price, Out of Position
Big blind defense vs button starts from a good price: the big blind has already put 1bb in the pot. Against a 2.5bb button open with the small blind folding, calling 1.5bb needs 27.3% equity; against 3bb, 30.8%. The catch: it plays the rest of the hand out of position, and a dominated hand realizes its equity poorly.
K♣9♦ in the big blind facing the button
The button opens to 2bb, the small blind folds and you are in the big blind with K♣9♦, 100bb deep. Fold, call or 3‑bet to 9bb?
See the answer
Calling costs 1bb for a 3.5bb pot: it needs 22.2% equity. Before the flop, K♣9♦ against hands the button opens:
| Button's hand | K♣9♦'s equity |
|---|---|
| T♠8♥ | 61.2% |
| Q♠7♠ | 60.5% |
| J♠8♠ | 58.6% |
| 7♥6♥ | 58.4% |
| Q♥T♥ | 54% |
| 5♠5♥ | 45.6% |
| A♥4♦ | 41.6% |
| K♥J♦ | 26.6% |
| A♠9♥ | 26.2% |
| A♦K♠ | 23.7% |
K♣9♦ has more than 22.2% against every one of these hands: folding gives that equity away. A 3‑bet to 9bb puts in 8bb more and, as a pure bluff, has to make the button fold 69.6% of the time; when called, it is often by hands like A♦K♠, K♥J♦ or A♠9♥, against which K♣9♦ drops below 27%. The expected answer is the call.
From a min-raise to 3bb: the price by open size
Button against big blind, small blind folded, 100bb:
| Button's open | What the big blind adds | Equity needed |
|---|---|---|
| 2bb (min-raise) | 1bb | 22.2% |
| 2.5bb | 1.5bb | 27.3% |
| 3bb | 2bb | 30.8% |
A min-raise gives the big blind its best price. The bigger the open, the more equity a call needs, and the fewer hands the big blind can defend.
Keep going
- Why the big blind acts last before the flop and first after it: poker positions.
- How the price is computed: pot odds.
- Why K♣9♦ suffers against A♠9♥: dominated hands.
- Calling or raising an open from another seat: cold call vs 3‑bet.
- Preflop decisions to practice: the preflop quiz.
- One spot every day: the daily poker puzzle.
- The seat just before: small blind strategy.
- What the button's raise has to fold out: blind stealing.
- The flop when you act first: playing out of position.
- Folding the big blind too often, and other mistakes: common poker mistakes.
For the rest of the hand from the big blind, see playing the big blind postflop.
Sources
- Every equity is computed by exact enumeration with the app's equity module, and every price with its pot odds module, checked on October 11, 2026.
- The answer to the spot follows rules written by the app's author; it does not come from a solver.