Team physician Dr. William Raasch instructed Narveson to bandage up the injured left thumb and try throwing.
"It actually wasn't too bad," Narveson said. "I had a protective little covering over it. I played catch, I didn't really do anything crazy. It was a way to exercise the arm and keep in shape."
Narveson hopes to come off the disabled list in time to pitch during a doubleheader at Pittsburgh on Aug. 22.
"I think we're still on track," he said. "It's just a matter of taking it day by day."