49ers place Christian McCaffrey on IR with calf tightness, Achilles tendinitis: Source

The San Francisco 49ers have placed star running back Christian McCaffrey on injured reserved with calf tightness and Achilles tendinitis, according to a league source. He will at least miss the next four games.

The 49ers ruled the two-time All-Pro out against the Minnesota Vikings on Friday, and coach Kyle Shanahan suggested San Francisco would consider IR. The soonest McCaffrey can return is Oct. 10 against the Seattle Seahawks.

Backup running back Jordan Mason started for the 49ers in last week’s win over the New York Jets, rushing for 147 yards and a touchdown on 28 carries.

McCaffrey won the 2023 Offensive Player of the Year and led the league in rushing yards last season with a career-best 1,459. Along with 14 rushing touchdowns, he added 564 receiving yards and a career-high seven receiving touchdowns.

How will San Francisco hold up without him?

McCaffrey’s absence means every other San Francisco tailback rises a notch in the pecking order. That includes rookie Isaac Guerendo, the fastest member of the group. Guerendo injured his hamstring on the first day of training camp and was out so long – nearly four weeks – that it seemed like he might not even make the team’s initial roster.

But he returned to the field in late August and looked so good in the preseason finale in Las Vegas that coaches were convinced he could handle a role in the regular season.

“He’d missed so much practice time, and his first time with pads on was that preseason game,” Shanahan said Friday. “I remember asking him in the team meeting after the game when was the last time he had pads on and he told me it was the Senior Bowl. So he was way behind in that stuff, but got a lot in the games and didn’t look overwhelmed. It seemed like the game wasn’t too big for him. And he’s been exactly like that ever since.”

The 49ers’ de facto No. 2 running back in Week 1 was Deebo Samuel, who lined up 10 times as a tailback and touched the ball – on carries and short throws – 13 times in that game. That type of workload might be difficult to sustain, and if it is, San Francisco may start giving carries to Guerendo, who becomes the first true tailback behind Mason.

Guerendo played three offensive snaps against the Jets but had no carries. He’s looking forward to getting the ball in his hands for the first time in a meaningful NFL game.

“Obviously, that’s what a running back loves,” he said. “Like I said, we have a great room and I’m excited to be a part of that.”

After Guerendo, the only other tailback on the active roster is Patrick Taylor Jr. The 49ers also have Ke’Shawn Vaughn on the practice squad. — Matt Barrows, 49ers beat writer

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(Photo: David Gonzales / USA Today)