Bailey, sidelined since July 20 with upper back spasms, threw out to a distance of 200 feet Tuesday afternoon, but Geren would like to see the A's reliever undergo a bullpen session before deeming him eligible to pitch.
That time could come as soon as Wednesday, and if all goes well, Geren said Bailey could potentially be available that night for the club's second contest of a three-game set in Texas.
"He's feeling good," Geren said, "but he's still day-to-day. There's a chance for tomorrow."
The A's could very much use their top reliever during the pivotal series with the first-place Rangers, who boast their own All-Star closer in Neftali Feliz. The young Texas hurler entered Tuesday's affair with an American League-leading 28 saves, including 19 in a row. Bailey, meanwhile, has not allowed a run in 13 of his past 15 appearances, a stretch over which he's compiled a 1.10 ERA. He has a 1.56 mark for the season, good for the sixth lowest among AL relievers.