San Francisco 49ers running back Jordan Mason left Sunday night’s game against the Dallas Cowboys with a shoulder injury and was considered questionable to return. He had briefly re-entered the game before leaving for good, replaced by rookie Isaac Guerendo.

The 49ers ultimately defeated the Cowboys 30-24. Guerendo finished with 85 rushing yards, averaging an impressive 6.1 yards per carry.

Mason has been dealing with an AC joint sprain since Week 6 against the Seattle Seahawks. After Sunday’s game, head coach Kyle Shanahan noted that Mason’s latest injury was to the same shoulder.

“JP (Mason) got beat up,” Shanahan said. “JP tried to come back, and he might have, but Isaac was rolling and doing well.”

In addition, linebacker Dee Winters suffered a concussion, wide receiver Deebo Samuel left with a rib injury and cornerback Renardo Green suffered an ankle injury. Shanahan stated he did not yet have details on the severity of Samuel and Green’s injuries.

Samuel was questionable to play against the Cowboys after a recent hospitalization for pneumonia, but was active for the game.

The 49ers have been hit hard by injuries this season, with ten players currently on injured reserve. The latest setback came with wide receiver Brandon Aiyuk, who is out for the season with a torn ACL and MCL.

San Francisco could see some players return after the bye week. Running back Christian McCaffrey, who has been sidelined this season with Achilles tendonitis, is expected to resume practice along with wide receiver Jauan Jennings, who has missed the last two games with a hip injury.

The 49ers’ next game is on November 10 when they take on the Tampa Bay Buccaneers at Raymond James Stadium.