Maryland v GA Tech

[EsqUmp]

I didn't see the play, but this appears to be the specific rule they needed to apply:

9.5.2 Offensive team personnel shall not reach out of the dugout or enter the field
and interfere with a defensive player attempting to field a fly ball. The field
belongs to the fielder, and the dugout belongs to the offensive team.

EFFECT—The ball is dead, and the batter is out. Each base runner must
return to the base legally occupied at the time of the pitch.