8♠7♠ BTN vs BB, turn on Q♠ 9♦ 4♣ 2♠, 100 bb

Best play: Raise

Why

The 2♠ turn on Q♠9♦4♣ brings in the spade flush draw and adds backdoor pressure to the board. Your 8♠7♠ now holds a spade flush draw (8♠7♠ plus Q♠2♠) plus a gutshot (a 6 makes 6‑7‑8‑9) — a combo draw with big equity but no showdown value. Facing the BB's turn bet, raising is the textbook semi-bluff: you fold out the BB's weak Q-x and middling pairs, and when called you have nine flush outs plus the straight outs to fall back on, applying maximum pressure with equity that prefers the pot big.

Key idea

A flush draw plus a gutshot is a premium semi-bluff raise on the turn — combine fold equity with two ways to improve.

Common mistake

Just calling the combo draw and giving up the fold equity, then realizing poorly when you miss with no showdown value.