"I'm just trying to work on the arm slot that will give me a little more depth and movement, just give me some of the break back to my pitches," Bannister said.
Bannister last pitched on Aug. 2 and has a 7-11 record and a 5.95 ERA. He doesn't know when he might return to the rotation.
"I have no idea," he said. "I think it's more important to get my stuff back."
Meantime, closer Joakim Soria need have no fear from Bannister.
"I'm not trying to take over Soria's job here," he quipped.