The batter (B1) hits a fair ball ground ball into the right field corner. As B1 runs from second base to third base, the right fielder throws to the second baseman, who then relays the throw toward third base. The relay throw would have made it to third base and B1 would have been easily tagged out, but the relay throw from the second baseman hits the field umpire. The ball then rolls into left field. B1 rounds third base and easily scores.

 

A. Since (in the umpire's judgment) the throw would have easily retired B1, B1 is out.

B. The last base that B1 had acquired before the umpire was struck was second base, so B1 is returned to second base.

C. The ball is dead when it strikes an umpire, so B1 is awarded third base.

D. The ball remains live, so play on -- B1's score counts.