Jordan Mason suffers injury vs. Seahawks: Latest news and updates for 49ers RB

The 49ers can ill-afford losing Jordan Mason to an elongated injury, but he had to exit Thursday Night Football against the Seahawks.

Update: Jordan Mason returned to the game at the start of the third quarter but played only briefly before spending the rest of the half on the sideline. It was later revealed Mason suffered a sprained AC joint, not believed to be serious.

Injuries have already been a massive problem for the San Francisco 49ers this season, highlighted by All-Pro running back Christian  inability to play yet this year because of Achilles issues.

Granted, McCaffrey's absence opened up the door for seldom-discussed backup rusher, Jordan Mason, who has taken the league by storm in Week 1 in the former's absence.

However, the Niners appear to have suffered yet another major blow to their backfield.

And it's Mason.

Jordan Mason suffers injury vs. Seahawks

Mason, who entered the week as the NFL's No. 2 rusher, was already making a serious dent against the Seattle Seahawks defense on Thursday Night Football, averaging 8.1 yards per carry on eight attempts, including a long of 38 yards.

At the 9:37 mark of the second quarter, and with San Francisco leading 13-0, Mason went down during a tackle and landed on his shoulder, which kept him on the turf for a period of time.

On the positive side, Mason was able to get up under his own power and didn't head into the blue medical tent. A few minutes later, though, the tailback walked into the locker room.

Related story: How to watch 49ers vs. Seahawks on Thursday Night Football

Amazon Prime's broadcast crew subsequently informed viewers that Mason was designated as questionable to return with a shoulder injury, going back into the locker room to get an X-ray.

Obviously, this is potentially dreadful news for an already banged-up 49ers squad that's missing McCaffrey and would have to turn to rookie running back Isaac Guerendo and special teams ace Patrick Taylor Jr. for the primary contributors on the ground.

Stay tuned for further updates.

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