During Sunday's game between the A's and the Seattle Mariners, both teams' locker rooms were flooded with raw sewage, forcing all of the players to shower in the Oakland Raiders' locker room, a team official said.
The leak began in the A's clubhouse early in the game and the sewage flowed into the team's laundry room, shower room, the umpires' shower room and lounge, the training room, and the visitors' clubhouse, said David Rinetti, A's vice president of stadium operations.
"We're fortunate it happened when it did because we have eight days to replace what we need to replace," he said.
The A's are not scheduled to play at the Coliseum again until June 25 when they begin an eight-game homestand.
The Oakland-Alameda County Coliseum Authority oversees the O.co Coliseum, which was built in 1966, and Rinetti said the building faces these sorts of issues throughout the year but normally not to this extent.
"The facility is old ... We do have drains that are clogged, we have to shut down areas of the stadium sometimes," Rinetti said. "It just shows why we need a new stadium."
The cause of the sewage overflow has not been determined but there is speculation the large crowd at Sunday's sold-out game may have contributed to it, Rinetti said.
The group "Save Oakland Sports" has been fighting to keep all three of the city's sports franchises in Oakland, but does agree with the team that the A's need a new stadium.
Group spokesman Jim Zelinski called the situation "unfortunate."
"The fact that the A's attendance is as high as it is after six years of uncertainty is nothing short of miraculous and it underscores (that) the fan base in Oakland and the East Bay is strong," Zelinski said.
A's relief pitcher Sean Doolittle tweeted about the sewage issue Sunday afternoon.
"After I checked out the new swimming pool in our locker room I got to see the Raiders clubhouse! Pretty cool!#CommitmentToExcellence," he wrote.
The A's have been waiting to hear from Major League Baseball on whether the team could be allowed to move to San Jose, which has already set aside a site for a new stadium. The San Francisco Giants currently own the territorial rights to Santa Clara County.