Mike Tolbert agreed to a deal with the Bills on Wednesday, but he will be a running back in Buffalo after playing fullback the past five seasons for the Carolina Panthers, a source told ESPN's Jordan Raanan.
The team announced Tolbert's addition but didn't specify how he would be used in their news release.
The deal is for one year and $1 million, a source told ESPN's David Newton.
Tolbert likely will be used as a third-down back behind starter LeSean McCoy in Buffalo. Tolbert will be reunited with Sean McDermott, the new Bills head coach who was the Panthers' defensive coordinator while Tolbert was with the team.
The Bills are also expected to sign fullback Patrick DiMarco on Thursday, a source told ESPN's Adam Caplan.
The Panthers released Tolbert, a three-time Pro Bowl selection, on Feb. 21.
Tolbert, 31, re-signed with the Panthers in 2016 on a two-year, $3.3 million deal with $700,000 guaranteed. Statistically he had one of his worst seasons, rushing 35 times for 114 yards and no touchdowns and catching 10 passes for 72 yards and one score.
Tolbert came to Carolina from San Diego in 2012. He made the Pro Bowl in 2013, 2015 and 2016.
He ran for a combined 12 touchdowns in 2012 and 2013 and the Panthers ranked among the NFL leaders in rushing in each of his five seasons in Carolina.
He posted a career-high 11 touchdowns rushing in 2010 with the Chargers and had 10 more total touchdowns in 2011.
Tolbert has played in 131 games with 44 starts in nine seasons. He has run for 2,402 yards and 33 touchdowns and caught 203 passes for 1,783 yards and 12 touchdowns.
The Associated Press contributed to this report.