Baltimore waived tight end Billy Bajema to make room on the roster for Monroe, who will wear No. 60 since his former number (75) was worn by Hall of Famer Jonathan Ogden.
Bajema, a nine-year veteran, has appeared in 12 games with the Ravens over the last two seasons. The remainder of his 118 career games have come with the Rams and 49ers.
Bajema has yo-yoed around the last several months, re-signing with Baltimore in June before being cut on Aug. 31 and re-signed on Sept. 4. Now he's back to being cut.