SAN FRANCISCO (AP) — Home plate umpire Adrian Johnson left the game between the Oakland Athletics and the San Francisco Giants in the fourth inning with an undisclosed injury.

The game was delayed before the start of the fourth inning Thursday when crew chief Angel Hernandez had to put on his home plate gear. Hernandez had been at second base before Johnson left. Paul Nauert and Mark Ripperger shared the base duties for the rest of the game.

Hernandez was hit in the mask by a foul ball in the first inning but stayed in the game.

Copyright 2014 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.