With quarterbacks Johnny Manziel and Brian Hoyer injured, the Browns will likely start rookie Connor Shaw against the Ravens with Thigpen backing him up. Thigpen knows Cleveland's offense after spending time with them during training camp this summer. He was waived on Aug. 12.
The 6-foot-1 Thigpen is in his seventh NFL season out of Coastal Carolina. He's appeared in 29 games and made 12 starts while playing for Kansas City, Miami and Buffalo.
Manziel injured his hamstring in Sunday's loss to Carolina and won't play in the finale. Hoyer has a shoulder injury and it's not yet known if he can play.
To make room for Thigpen, the Browns waived fullback Ray Agnew, who started nine games and appeared in 12.
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