The 49ers announced they have promoted defensive back Greg Mabin from the practice squad. They signed cornerback Tarvarus McFadden to take his place on the practice squad.
Mabin, 25, has played six games with one start this season with the 49ers. He has 10 tackles and a forced fumble.
The 49ers waived him Oct. 30 before signing Mabin back to the practice squad.
He originally joined the 49ers last season, signing to their practice squad Oct. 18 after the Bills cut him before earning a promotion Nov. 1. Mabin has played 13 games over the past two seasons with Buffalo and San Francisco, making 11 tackles, two pass breakups and forcing a fumble.