49ers RB Christian McCaffrey's backup is injured, and CMC's health just became that much more crucial

Every report on Christian McCaffrey's health this summer has been a positive one. It better stay that way.

Because the San Francisco 49ers' running back depth chart behind CMC has thinned out considerably.

Head coach Kyle Shanahan told reporters Monday that RB Isaac Guerendo is expected to miss "a few weeks." He has a shoulder injury.

That comes after the 49ers traded away fellow talented backup Jordan Mason early in the offseason to the Minnesota Vikings.

Part of the Mason trade had to do with a trust for Guerendo. Now, San Francisco just has to hope the second-year back can heal up in time for the regular season.

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It's an iffy depth chart behind McCaffrey now, and his backup spot is a key role. He missed nearly the entire 2024 season with two different injuries, a big reason the 49ers stumbled to a 6-11 season.

Behind CMC right now are a pair of inexperienced backs. The 49ers have fifth-round rookie Jordan James, and they have Patrick Taylor Jr.

San Francisco also signed veteran Ameer Abdullah last week. Maybe they saw this coming, or maybe they lucked into it, but at least Abdullah brings ample NFL experience.

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The 49ers may provide an indication of how they're feeling about their RB depth in the days ahead. If they sign another veteran back out of free agency, it likely signals that Guerendo's injury may be a close call for the start of the season. They also will need enough backs just to get through preseason games in one piece, too.

If the 'Niners stay put, it's a good indicator that Guerendo is going to be OK. That's not the most important running back health in the Bay Area, of course, but for as long as McCaffrey is healthy, the 49ers just need to make sure they've got somebody behind him to plug-and-play in case of emergency. That guy this season is supposed to be Guerendo, but right now he's hurting, and so the question marks get a little bigger.

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