San Francisco 49ers

Arik Armstead’s season ends as 49ers place him on IR

The 49ers on Tuesday placed defensive lineman Arik Armstead on injured reserve, ending his season after he was forced out of the last two games because of a painful left shoulder.

Armstead hurt his shoulder during training camp Aug. 7, and the injury has been nagging. He played only a handful of snaps in Sunday’s loss to the New Orleans Saints before aggravating the injury while reaching out to tackle running back Tim Hightower. He also was forced to leave the Oct. 23 loss to the Tampa Bay Buccaneers.

Armstead has said he might need surgery on the joint. It’s not known if that has been scheduled.

Despite his staggered start, Armstead is tied with Ahmad Brooks for the team lead in sacks with 2 1/2 . The 49ers hoped Armstead and his former Oregon teammate DeForest Buckner, both 6-foot-7 first-round picks, would be twin towers vexing opposing passers.

They started the last four games together, but Armstead has not been at full strength during the season. Meanwhile, the 49ers’ defense ranks last in yards allowed per game (428.0). Their run defense, giving up a league-high 193.0 yards a game, is on pace to allow 3,088 yards, which would be the second most in NFL history.

With Armstead gone, Buckner and Quinton Dial could start at defensive end with Glenn Dorsey taking over at nose tackle. Tony Jerod-Eddie and rookie Ronald Blair likely will fill in as they did Sunday.

The 49ers filled Armstead’s roster spot with defensive tackle Chris Jones, who played seven games with the Miami Dolphins this season and was waived Monday. Jones, a sixth-round draft pick by the Houston Texans out of Bowling Green in 2013, also spent two seasons with the New England Patriots, starting 23 games.

Redmond won’t play – Cornerback Will Redmond will not be elevated to the active roster from injured reserve, the latest blow to general manager Trent Baalke’s philosophy of drafting players coming off ACL injuries.

Redmond was a highly regarded cornerback at Mississippi State who suffered a knee injury in October 2015. The 49ers drafted him in the third round with Baalke noting Redmond’s injury was standard as far as ACL issues go and he was ahead of schedule in his rehabilitation.

Baalke insisted Redmond not only would play this season but would participate in training camp.

“Very comfortable with where he’s at and very comfortable that he’ll be ready to go come training camp,” he said after Redmond was drafted.

But the cornerback was only a partial participant in training camp, did not play in the preseason and went on injured reserve in early September. Last month, the 49ers designated him as their player who could return from injured reserve and play this season.

The earliest he could have played was Sunday against the Saints. Redmond, however, did not progress enough in recent weeks and will not be activated this year. He practiced with the team Tuesday, the last day he was eligible to do so. The 49ers are now unable to use the return-from-IR designation on any other players.

Since 2013, the 49ers have drafted seven players coming off college ACL injuries. Some, such as running back Marcus Lattimore, are no longer in the league. Others such as linebacker Tank Carradine and cornerback Keith Reaser remain on the squad but are not starters.

Et cetera – The 49ers reshuffled the bottom of their wide receiver corps, promoting former Cal receiver Chris Harper to the active roster and releasing Keshawn Martin, who hadn’t been active for a game since fumbling a kickoff against the Buffalo Bills on Oct. 16. The team filled Harper’s spot on the practice squad with rookie receiver Mose Frazier, who played at Memphis and signed with the Denver Broncos as an undrafted free agent.

▪ The team held its first practice of the week without receiver Torrey Smith (back) and offensive tackle Joe Staley, who might have been taking a veteran rest day.

▪ Running back Carlos Hyde, who has missed the last two games because of a shoulder injury and has not played since Oct. 16, again practiced in a blue jersey that signals he is to avoid contact. DuJuan Harris played well in Hyde’s absence Sunday, gaining 59 yards on 10 carries.

Matt Barrows: @mattbarrows, read more about the team at