49ers-Lions: Shanahan talks RB Trey Sermon’s status; RB Elijah Mitchell recaps his NFL debut

Elijah Mitchell finishing the day with over 100 rushing yards while Raheem Mostert and Trey Sermon watched from the sidelines was probably not the result anyone expected at running back for the San Francisco 49ers in their 41-33 Week 1 win over the Detroit Lions on Sunday.

But that's exactly how things transpired after the third-round pick Sermon was an unexpected healthy scratch and Mostert left the game early due to a knee injury.

Mitchell, who was selected in Round 6 of the 2021 NFL Draft out of the University of Louisiana, finished the day with 19 carries for 104 yards, with one of those carries going for a 38-yard touchdown. Mitchell was impressive for the 49ers during training camp and the preseason when he was healthy, so his success when given the opportunity didn't come as a big surprise to head coach Kyle Shanahan.

"I thought he did a real good job," Shanahan said. "That's kind of what we expected him to do. But it's always tough in your first game and stuff. He went in there and didn't hesitate and ran the ball well."

Mitchell's involvement wasn't something many outside of 49ers facilities expected given the fact Sermon was seemingly higher in the pecking order during the preseason. But Shanahan said Sermon's status was never etched in stone, as was demonstrated on Sunday.

"We rotate everybody with the ones, twos and threes throughout camp and stuff. Nothing is ever firm, to tell you the truth," Shanahan said.

Also suiting up along with Mitchell and Mostert was second-year back JaMycal Hasty, who finished with a three-yard touchdown run and one catch for 15 yards.

"We only dressed three backs," Shanahan said. "You always try to do four, but those were the three after doing training camp and stuff that we felt were the three we were going to go with."

Mitchell told reporters after the game he was ready when his name was called on Sunday due to the teaching he's been given by running backs coach Bobby Turner.

"I was definitely ready for it. Coach Bobby T, he coaches everybody the same and keeps us all ready to go because things happen," Mitchell said.

And while he gave an assist to Turner for keeping him ready, Mitchell also gave some props to his blockers for helping him on his touchdown run -- which is certainly warranted given the size of the hole he was given to run through.

"As soon as I caught the ball, I saw George [tight end George Kittle] and them on the outside blocking their butts off," Mitchell said. "I saw the hole so I just had to hit it."