What is the difference between obstruction and interference in softball?
A · Advanced · Pitching and base running · 4 of 6Obstruction is by the defence: a fielder without the ball gets in a runner's way. The play continues and the umpire then gives the runner the base they would have reached. Interference is by the batting team: a runner or team member hinders a fielder making a play. The ball is dead at once and somebody is out.
How it works
- Obstruction: a fielder impedes a runner while "not in possession of the ball" and not fielding a batted ball.
- Also obstruction: a fake tag without the ball, and pushing a runner off a base.
- The call: a delayed dead ball. Play goes on to its end.
- The award: the base or bases the runner would have reached, in the umpire's judgement.
- Protected: an obstructed runner cannot be put out between the two bases where it happened.
- Catcher's obstruction: hindering the batter's swing. The batter gets first base unless the batting team prefers the play.
- Interference: an offensive player or team member who "impedes, hinders or confuses a defensive player attempting to execute a play".
- The call: the ball is dead, the offender is out and other runners go back.
- Hit by a batted ball: a runner struck off the base by a fair ball no fielder has touched is out, if a fielder had a chance to make an out.
- To stop a double play: the runner behind may be called out as well.
- Crashing: a runner who stays upright and deliberately crashes into a fielder holding the ball is out. If flagrant, they are ejected.
- The right of way: a fielder fielding a batted ball has it. A runner may leave the base path to go round.
The glossary has interference, obstruction, the tag out, the base runner, the catcher and the dead ball.
Tricky cases
A shortstop with no ball pretends to tag a runner, who slows down. What is the call?
Obstruction. A fake tag is a form of obstruction, and the runner does not have to stop or slide for it to be called.
A runner is obstructed between second and third and is then tagged out sliding into third. Out?
No. The ball becomes dead and the runner is given the base they would have reached without the obstruction.
A ground ball hits a runner between first and second before any fielder touches it. What happens?
The runner is out if a fielder had an opportunity to make an out. The ball is dead and the batter is given first base.
A catcher has the ball and is waiting. The runner lowers a shoulder and runs into the catcher. Safe if the ball comes loose?
No. A runner who remains on their feet and deliberately crashes into a fielder holding the ball is out.
Why the rule exists
Runners and fielders share the same strip of ground. The two rules divide it: the fielder owns the space while fielding the ball or holding it, and the runner owns the path at every other time. The different timing of the calls means the side that was wronged never loses by it.
Where it differs
| Where | What changes | Source |
|---|---|---|
| Obstruction | Delayed dead ball, then bases awarded | WBSC Softball Rule 5.10.2 |
| Interference | Dead ball at once, an out | WBSC Softball Rule 5.10.3 c |
| World Cups | Contact above the waist is judged an attempt to dislodge the ball | WBSC Softball World Cup Regulation C7.5 f |
| Flagrant contact | Ejection, even if the runner is safe | WBSC Softball World Cup Regulation C7.5 f |
From the rule book
World Baseball Softball Confederation, Official Rules of Softball: Fast Pitch (2026-2029), Rules 5.1.17, 5.1.30, 5.1.32, 5.5.1 d and e, 5.10.2, 5.10.3 c and 5.10.4. WBSC, Softball World Cups Tournament Regulations (revised 3 March 2026), C7.5 f. Checked 14 October 2026. Official document: WBSC Official Rules of Softball, Fast Pitch, 2026-2029 (PDF).