CHARLOTTE, N.C. — After Carolina Panthers backup quarterback Matt Moore injured his left leg in the final preseason game last week, he had two X-rays and an MRI that revealed no broken bones.

Cleared to practice today, Moore attempted to push off on his leg and felt something pop. X-rays revealed a broken fibula, and Moore is out indefinitely.

"He had gone out with the trainers and felt good (Tuesday)," general manager Marty Hurney said. "But something happened at practice. Hopefully he'll be back as quick as he can."

While Hurney said Moore will not be placed on injured reserve, the Panthers did re-sign Brett Basanez to the practice squad Wednesday afternoon and released defensive end Angelo Craig. He could serve as the No. 3 QB behind starter Jake Delhomme and backup Josh McCown, who was acquired from Miami a day after Moore was injured.

"Matt won't practice for a while. We're going to have three quarterbacks practice," Hurney said. "Brett knows our system and can step in at any time. That was an obvious move for us to do."

Moore went 2-1 as a starter for the Panthers last season as an undrafted rookie. But he struggled in the preseason, not leading the Panthers to a touchdown, and was expected to drop to third-string behind McCown.