Stop me if you’ve heard this before: The San Francisco 49ers have an injury at the running back position. The 49ers entered Sunday’s Week 1 game against the Detroit Lions with Raheem Mostert set to carry the load in the backfield, but Mostert carried the ball just two times before exiting the game with a knee injury. Mostert is now expected to miss approximately eight weeks of action.

Head coach Kyle Shanahan must now move forward without his presumed lead dog, but the good news is that there’s a clear-cut candidate to lead the backfield in the weeks ahead. And no, I’m not talking about third-round pick Trey Sermon, who was surprisingly a healthy scratch on Sunday.

Elijah Mitchell, a sixth-round rookie out of Louisiana, absolutely stole the show for the 49ers in Week 1 and should be the team’s starting running back for Week 2 and beyond.

Mitchell stepped up to the plate in a major way following Mostert’s injury by rushing for 104 yards and a touchdown on just 19 carries. Detroit’s run defense had no answer for Mitchell, who averaged 5.5 yards per carry in his NFL debut.

The highlight of Mitchell’s day was this 38-yard touchdown run.

https://twitter.com/NBCS49ers/status/1437112088598437889

Shanahan was clearly impressed with his first-year player.

“I thought he did a really good job for us,” Shanahan said during his post-game presser. “He did what we expected him to do, but it’s always tough to do it in your first game. He went in there, didn’t hesitate, and ran the ball well."

https://twitter.com/JL_Chapman/status/1437177844430299137

It wasn’t a total surprise for those of us who pegged Mitchell as a sleeper back in the 2021 NFL Draft. Many of the positive traits we saw from Mitchell throughout his time at Louisiana were on display in San Francisco’s Week 1 victory. Mitchell ran the ball with the physical mindset he’s known for. He’s a punishing runner that’s always fighting for extra yards. Mitchell was decisive and showcased great vision with the ball in his hands.

It can be tough to predict what Shanahan will do with his backfield on a weekly basis, but Mitchell certainly earned the right to be the first man up in Week 2, just as he was against the Lions in Week 1. JaMycal Hasty was also active vs. the Lions but was out-touched by Mitchell to the tune of 19-2.

Sermon is the real wildcard here. He’s the running back we all expect to take over this backfield at some point, and he will almost certainly suit up for his first professional game against the Philadelphia Eagles this Sunday. There are some tough decisions to be made here, but If Shanahan is willing to ride the hot hand, then Mitchell should receive the bulk of the work going forward.

Read our exclusive interview with Elijah Mitchell here. You can also read our scouting report on Mitchell here.