Devlin, 6-foot-3 and 225 pounds, lasted just one month with the Bears in the offseason. He has not thrown a pass in the NFL.
Devlin, 27, will be the team's third arm in practice heading into Saturday's third preseason game in Tampa Bay. Coach Mike Pettine had said Wednesday that anyone signed would probably not be ready to play against the Bucs. That playing time would be shared by Josh McCown and Thad Lewis. How long Devlin lasts with the team might depend on Manziel's elbow.
The Browns did have the option of considering Terrelle Pryor as a quarterback, but the team seems committed to seeing what Pryor can do at wide receiver.