The Oakland Athletics activated shortstop Bobby Crosby from the 15-day disabled list Monday, and optioned struggling infielder Keith Ginter to Triple-A Sacramento. Crosby, last season's AL Rookie of the Year, played on Opening Day before going on the disabled list April 6 with two broken ribs. He went 1-for-12 on a three-day rehabilitation assignment with Sacramento last weekend, but the A's couldn't wait any longer to get help for their struggling offense. "I think physically I'm definitely ready," Crosby said before the A's played the Tampa Bay Devil Rays to begin a seven-game homestand. "Mentally, I think it will be a little tougher on me. I didn't perform the way I wanted to in Triple-A. I think I can benefit the team more by playing."