His procedure was performed in Philadelphia by Dr. William Meyers, a sports hernia specialist who has previously operated on several professional athletes, including the NFL's Donovan McNabb. He is expected to face a recovery time of three weeks.
That timeline has Geren "hopeful" Jackson might be able to return before season's end, saying he could "still be available at the end." Given his history, though, the A's likely won't rush him.
The outfielder has played in just 60 games this year -- 18 of them with the A's, who acquired him via trade from the D-backs in June. He missed a handful of time with both teams due to a strained right hamstring, which most recently had him on the disabled list until Aug. 16 -- four days before he was placed back on it again.
In the meantime, the A's are expected to continually rotate a handful of players in the outfield with Coco Crisp and Rajai Davis representing everyday mainstays. Among those likely to be playing musical chairs are Jack Cust, Gabe Gross, Matt Carson and Jeff Larish.