Feyereisen (biceps) will throw a bullpen session Saturday, Neil Solondz of the Rays Radio Network reports.
Feyereisen landed on the injured list July 21 due to biceps tendinitis, but he underwent an MRI that didn't reveal any structural damage. The right-hander's weekend return to the mound was expected, and he'll now begin the process of ramping up his workload before the team doctors clear him to return to game action.