OBR / FED Rules Differences

If a called ball on a checked swing is appealed (by the manager or catcher only), plate umpire is required to ask for help, then is obligated to take the partner's ruling.

If a called ball on a checked swing is appealed, the plate umpire may ask for help on checked swing appeal, but is not required to do so.

When the momentum of a batter's swing carries the bat around and contacts the catcher or his equipment, this is backswing interference. The ball is dead, and runners, if moving, must return. There is no penalty so long as deemed by umpire to be not intentional.

Ball immediately dead; runners return; batter is out if impeding play on runner. If no play on runner, dead ball and runners return.

FED draws a distinction between backswing interference and follow-through interference:

Follow-through interference is when bat hits catcher after batter has swung at pitch and hinders catcher's play on a runner.

Backswing interference is when a batter contact the catcher or his equipment prior to the pitch.

Designated hitter allowed for pitcher only; double-switch is allowed, but doing so kills the DH.

Designated hitter may bat for any player; both retain same position in batting order. May not do multiple-subs to change player's positioin in the batting order. If DH enters game defensively, this kills DH.

Runner abandons effort to advance when he leaves the dirt circle surrounding home plate.

Runner abandons effort to advance when he enters the dugout, or (with two outs) before all fielders leave the diamond.