A's closer Andrew Bailey confirmed the obvious Sunday, that he'll start the season on the 15-day disabled list because of a forearm strain.

More unexpected was manager Bob Geren mentioning Grant Balfour as a fill-in closer option along with Brian Fuentes.

Fuentes, owner of 187 career saves, was the assumed heir apparent after Bailey hurt his forearm March 14, though Geren had not officially christened Fuentes the closer.

"I could use either one," Geren said. "Fuentes has the most experience. I feel comfortable with him. I also know Grant can do it if it's better to use someone else in a different inning."

Fuentes, 1-1 with a 5.87 ERA in nine spring appearances, didn't allow a run through his first six appearances but was touched for six hits and five earned runs over his next two (1?1/3 IP). The lefty retired both hitters he faced Friday against the Los Angeles Angels.

Geren is confident that Balfour, 1-0 with a 7.71 ERA in 10 games, has worked out some mechanical issues.

The right-hander has just eight saves in 261 major league appearances, but he's averaged 10.29 strikeouts per nine innings over the last three seasons.

Bailey played catch Sunday morning, the first time he's thrown since his injury.