A ground ball hit back to the mound by Eric Chavez was fielded by Rich Harden, who ran to the first base bag. First base umpire Paul Schrieber called Chavez out. Chavez immediately asked if Harden had touched the bag, and Oakland manager Bob Geren came out to argue.
The replays show it was close as Harden looked away from the bag as he approached first.
The reversal was made after the umpires huddled, and the play was scored an error on Harden. Washington came out and argued, and it didn't take him long to get ejected.
It's the second time Washington has been ejected this road trip. He was thrown out in Friday's extra-inning win against Seattle.
Bench coach Jackie Moore is the manager for the rest of the game.