Gillmore, 24, has missed the past two weeks with back and shoulder injuries.
Gillmore had 33 catches for 412 yards and four touchdowns this season, his second in the NFL. He was expected to fill the void on offense left by rookie Nick Boyle, who was suspended four games after violating the NFL’s drug policy.
The team also announced Monday that it signed free-agent outside linebacker Chris Carter to replace Gillmore on the 53-man roster. Carter was released by the Cincinnati Bengals last week after playing 13 games with the team this season, primarily on special teams.
The Ravens (4–10) host the Pittsburgh Steelers (9–5) on Sunday at M&T Bank Stadium.