Gutshot

Inside straight draw — 4 outs

Definition

A gutshot (inside straight draw, "belly buster") is a straight draw where only one rank completes the straight — the missing card sits in the middle. Four cards provide it: 4 outs. Probabilities: about 8.5% to hit on the next card, ~16.5% from flop to river — the rule of 2 and 4 gives 8% and 16%, very close to the real numbers. On its own, a gutshot is a weak draw: 4 outs almost never justify calling big bets. Its real value is as a supplement — combined with an overcard, a backdoor flush draw or a pair, it turns a mediocre hand into a fine continue or semi-bluff candidate. Solvers love bluffing with gutshots: enough equity to get there sometimes, not enough showdown value to prefer checking. Special case: the double gutshot (two inside draws at once, e.g. J9 on K-T-7), which counts 8 outs like an OESD but stays far better disguised — the two completing cards don't jump out at a glance.