49ers RB Christian McCaffrey placed on injured reserve, will miss at least 4 games

San Francisco 49ers running back Christian McCaffrey is being placed on injured reserve, the team announced on Saturday. McCaffrey will now miss at least the next four games while recovering from Achilles tendinitis and calf tightness.

McCaffrey was a late scratch in last Monday's season opener, with the 49ers announcing that he would be inactive just a few hours before kickoff. The 49ers went on to handily beat the New York Jets despite missing the three-time Pro Bowl running back.

On Friday, McCaffrey was ruled out of San Francisco's Week 2 matchup against the Minnesota Vikings with the injuries. In a news conference the same day, 49ers head coach Kyle Shanahan told reporters that they were considering placing him on injured reserve, adding that McCaffrey had been in a lot of pain during practice on Thursday.

"It's on and off, but with [Thursday] having the most pain, it's something we're going to be discussing the next 24 hours," Shanahan said.

It's a tough blow for the 49ers to lose McCaffrey, who has been a crucial piece of the San Francisco offense since joining the team in 2022. The 28-year-old running back is the reigning AP NFL Offensive Player of the Year, having led the league with 2,023 yards from scrimmage, including 1,459 rushing, and 21 total touchdowns.

By being placed on IR, the earliest that McCaffrey could return would be Week 6 against the Seahawks. The 49ers will allow him time to recover before reassessing him in mid-October.

Jordan Mason will be San Francisco's starting running back going forward.