Why do runners go back to their base when a fly ball is caught?
I · Intermediate · Running the bases · 4 of 9Because the rule requires it. When a fly ball is caught, each runner must be touching their base at or after the moment the ball is first touched before they may advance. A runner who left early must get back before the ball does. If the defence gets the ball to that base first and appeals, the runner is out.
How it works
- Retouch: a runner must retouch the base "after a fair or foul ball is legally caught".
- From the first touch: the runner may leave when the fielder first touches the ball, not when it is held.
- Then go: after retouching, the runner may try to advance at their own risk.
- Left too soon: the runner is out if they or the base is tagged before they get back.
- An appeal play: the defence must make the play and claim it, before the next pitch or play.
- Foul balls count: a caught foul fly works the same way.
- No running start: a runner may not start from behind the base to get a run at it.
- Sacrifice fly: a fly ball caught deep enough for a runner to tag up and score.
- Fielder falls out of play: if a fielder catches the ball and steps or falls into a dead-ball area, each runner advances one base.
The glossary has the fly ball, the catch, the sacrifice fly, the appeal play, the base runner and the double play.
Tricky cases
A runner on third leaves as soon as the outfielder touches the ball, though the fielder bobbles it before holding on. Legal?
Yes. The retouch is timed from when the ball is touched in making the catch.
A runner on first runs on the pitch and a line drive is caught. The ball is thrown to first before they return. What is the call?
Out, on the defence's appeal at first base. It is not a force play, so a run that scored before that out can count.
A runner leaves early, nobody on the defence notices and the next pitch is thrown. Can they appeal afterwards?
No. An appeal must be made before the next pitch or any play or attempted play.
A foul fly is caught near the stands with a runner on third. Can the runner score?
Yes, after tagging up. A caught foul ball is in play.
Why the rule exists
Without it, runners would set off the moment the ball was hit and a caught fly would cost the batting side nothing. Making runners wait for the catch turns every fly ball into a small race between an outfielder's arm and a runner's legs. Timing it from the first touch stops a fielder from juggling the ball to hold runners back.
Where it differs
| Where | What changes | Source |
|---|---|---|
| Fly ball caught | Runners must retouch before advancing | WBSC Baseball Rule 10.7.5 |
| Fly ball dropped | Runners may run without retouching, and may be forced | WBSC Baseball Rule 10.7.6 |
| Infield fly | Batter is out; runners may advance at their own risk | WBSC Baseball Rule 6.45 |
| Catch carried into a dead-ball area | Runners advance one base | WBSC Baseball Rule 8.1.3 |
From the rule book
World Baseball Softball Confederation, Official Rules of Baseball (2025-2026 edition), Rules 6.69, 8.1.3, 10.7.5 and 11.1. Checked 14 October 2026. Official document: WBSC Official Rules of Baseball 2025-2026 (PDF).