Infield fly rule after the fact

[BretMan]

This is straight from the published ASA Case Book, the sole purpose of which is to clarify and explain the playing rules.

With one out and R1 on second base, R2 on first base, B3 hits an apparent infield fly. The umpire does not call "infield fly". The fly ball is not caught and in the confusion both R1 and R2 are tagged off base resulting in three outs.

RULING: The infield fly should have been in effect. Failure of the umpire to invoke the infield fly placed the runners in jeopardy. This is correctable by calling the batter out and returning the runners to their respective bases (see rule 10-3C).

It can't be much more plain than that.