The Ravens’ already beleaguered defense suffered another blow Wednesday.

Defensive tackle Michael Pierce has been placed on injured reserve, the team announced. The nine-year veteran suffered a calf injury in Baltimore’s loss to the Browns on Sunday in Cleveland. He will miss at least the next four games, but the injury will not end his season, according to coach John Harbaugh.

Already, Baltimore is dealing with several injuries along its defensive front. Brent Urban suffered a concussion Sunday and defensive tackle Travis Jones is dealing with an ankle injury. Neither practiced Wednesday ahead of Sunday’s game against the visiting Denver Broncos.

Pierce, who also missed the Ravens’ Week 4 win over the Buffalo Bills with a shoulder injury, has 15 tackles and one sack through seven games while playing behind Jones in the rotation.

The Ravens’ secondary was a point of contention coming out of Sunday’s loss, having dropped three interceptions. Wednesday brought reinforcements. Takeaways leader Marlon Humphrey (knee), who logged two picks against the Tampa Bay Buccaneers the previous week, returned to practice in a limited capacity. So did rookie Nate Wiggins (shoulder/illness), who trails only Humphrey in pass deflections.

Harbaugh said both had “really good practices” and they’re “day-to-day.” He’s hopeful they’ll be available Sunday.

Running back Keaton Mitchell was also a full participant for the first time this season, fighting back from a torn ACL he suffered last December. The 2023 undrafted free agent broke out last year, rushing for 396 yards and two touchdowns in eight games.

Quarterback Lamar Jackson (back/knee), running back Rasheen Ali (ankle) and cornerback Arthur Maulet (neck) all did not practice on Wednesday. Defensive tackle Broderick Washington (knee) was a limited participant.

On Monday, the Ravens signed veteran nose tackle Josh Tupou, who spent much of the summer in Baltimore, to the practice squad. He could be a game-day elevation Sunday.

For Denver, safety P.J. Locke (thumb) did not practice Wednesday after missing Sunday’s win over the Carolina Panthers. Nor did right tackle Mike McGlinchey (knee), who is Pro Football Focus’ 17th highest-rated tackle in the NFL.

Broncos defensive end Zach Allen (rest), fullback Mike Burton (foot) and safety Delarrin Turner-Yell (knee) were all limited. Turner-Yell returned to practice, opening his 21-day window to be activated off the physically unable to perform list. Tackle Alex Palczewski (ankle) and cornerback Pat Surtain II (ankle) were both full participants.

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