Gutshot

Also known as: gutshot straight draw, inside straight draw, belly buster, gutter

An inside straight draw needing one specific rank to complete — 4 outs, roughly 8.5% per street.

A gutshot (inside straight draw) needs one specific rank, filling a gap in the middle of four cards. It has 4 outs. Compare the open-ended straight draw, which is open at both ends for 8 outs.

Using the Rule of 2 and 4:

• Per street (one card to come): \(4 \times 2 = 8\%\). Exact: \(\dfrac{4}{47} \approx 8.5\%\).
• Flop to river (two cards): \(4 \times 4 = 16\%\). Exact: about \(16.5\%\).

Those are the naked numbers. A bare gutshot rarely has the pot odds to draw passively, but it's a fine semi-bluff component — it adds equity to a bluff and combines well with overcards or a backdoor flush draw to lift you into proper float and check-raise territory. A double gutshot (two separate inside draws) plays as 8 outs, like an OESD.

Value gutshots higher when they make the nuts and when implied odds are strong (deep stacks, hidden draw). Discount them when reverse-implied or when the straight isn't to the nuts.