[Rich Ives]

Originally Posted by greymule

I once saw Hector Lopez hit a walk-off "ground rule" double. He touched 1B and went directly to the dugout. He was credited with a single.

I met him once many years later and forgot to ask him whether he remembered it.

He probably only would have been credited with a single anyhow:

10.06

(f) Subject to the provisions of Rule 10.06(g), when a batter ends a game with a safe hit that drives in as many runs as are necessary to put his team in the lead, the official scorer shall credit such batter with only as many bases on his hit as are advanced by the runner who scores the winning run, and then only if the batter runs out his hit for as many bases as are advanced by the runner who scores the winning run.

Rule 10.06(f) Comment: The official scorer shall apply this rule even when the batter is theoretically entitled to more bases because of being awarded an “automatic” extra-base hit under various provisions of Rules 6.09 and 7.05.

The official scorer shall credit the batter with a base touched in the natural course of play, even if the winning run has scored moments before on the same play. For example, the score is tied in the bottom of the ninth inning with a runner on second base and the batter hits a ball to the outfield that falls for a base hit. The runner scores after the batter has touched first base and continued on to second base but shortly before the batter-runner reaches second base. If the batter-runner reaches second base, the official scorer shall credit the batter with a two-base hit.