Christian McCaffrey injury updates: When will 49ers running back play again?

Week 1 of the NFL season brought myriad surprises: including the New England Patriots taking down the Cincinnati Bengals and the Chicago Bears looking worse with Caleb Williams than they did with Tyson Bagent a year ago.

But the most surprising of them all was Christian McCaffrey's last-minute scratch from the 49ers' "Monday Night Football" game against the New York Jets.

McCaffrey gave way to undrafted backup Jordan Mason, who went off for 147 yards and a touchdown. While that was great for everyone who started Mason in their fantasy leagues, it wasn't so great for everyone who took McCaffrey first overall. The star's injury appears to be worse than originally thought, and it's got everyone wondering when he will take the field again.

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Here are the latest updates concerning McCaffrey's ankle injury.

Why did Christian McCaffrey sit out?

Bay Area reporter John Dickinson reported Tuesday that McCaffrey's injury was related to his Achilles, and that it has flared on and off recently.

This type of injury makes Mason's statement that he knew he would be in the 49ers' starting lineup on Friday more understandable. Reports pointed out that McCaffrey was removed from practice Friday due to the ankle injury, but that no one was overly concerned about it at the time.

Mason was likely informed that he might be forced into the starting role after McCaffrey's departure, but not confirmed until the day of the game.

Is McCaffrey going to play Week 2?

McCaffrey's status for Week 2 against Minnesota is unknown. ESPN's Adam Schefter reported there is a "real chance he's not gonna play on Sunday."

As it stands, McCaffrey's lingering injury is not a good sign. His ankle has bothered him for a month now and, although there have been "no setbacks" (per 49ers coach Kyle Shanahan), the uncertainty whether it will bother McCaffrey each day does not bode well for his chances of returning in the short term.

Minnesota's home stadium, U.S. Bank Stadium, is also a turf field, which could be troublesome for McCaffrey's ankle if not fully healed. San Francisco clearly doesn't need McCaffrey at the moment, so the team could be inclined to keep him sidelined.

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Kyle Shanahan responds to Adam Schefter report

When asked about the validity of Schefter's report that McCaffrey was likely to miss Week 2, Shanahan told reporters, "That person must've been God."

When do the 49ers play next?

The 49ers will be on the road in Week 2 for a matchup against the Minnesota Vikings on Sunday. Kickoff is scheduled for 1 p.m. ET.

This article originally appeared on USA TODAY: When will Christian McCaffrey play again? Updates on star's injury