However, Duchscherer, who has been on the disabled list since Aug. 19, could potentially pitch again this season, contrary to what had previously been reported.
"He's shut down," Geren said on Friday. "He's going to go to see [Dr. Thomas Byrd, who] did his surgery last year, to get reevaluated."
Geren added on Saturday afternoon: "My preference and his preference, I'm sure, is to get back out there before the season ends. For his own sake, I'd love for him to pitch a few more times."
Duchscherer, who remained positive about the prospect of getting back on the mound this season, will visit Dr. Byrd, the same doctor who operated on the 30-year-old last July, on Monday in Tennessee to decide his next course of action.
"I can get up to 80, 85 percent," Duchscherer said Thursday after his unsuccessful side session, "but as soon as I get anywhere close to game speed, it starts to pinch in there again, so I had to shut it down."
Prior to going on the disabled list, Duchscherer, an All-Star, was the A's best starter with a 10-8 record and a 2.54 ERA.
Duchscherer originally injured the hip in May of 2007 and underwent the season-ending surgery in July of last season, but was productive this season -- the first as a starter for him -- until the hip became an issue again 17 days ago.
Amanda Comak is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.