Niners running back Jerick McKinnon, who missed all of last season with a torn right ACL, has been activated from the physically unable to perform list, the team announced Tuesday.

McKinnon, 27, signed a four-ye

ar, $30 million free agent deal with the 49ers last offseason and was projected to be the team's No. 1 back before suffering the injury on Sept. 1.

He opened training camp this year on the PUP list after suffering a setback in his rehab process when the surgically repaired knee flared up, 49ers GM John Lynch said early in camp.

In four seasons with the Vikings, McKinnon had 474 carries for 1,918 yards and seven touchdowns. He added 142 receptions for 421 yards and five TDs.

Before his injury, McKinnon was projected to be a pass-catching weapon out of the backfield after recording 51 receptions in 2017.

Now he joins a crowded running back picture in San Francisco.

Third-year back Matt Breida stepped up to fill the void McKinnon's injury left in 2018, rushing for 814 yards (5.3 per carry) and three touchdowns. The team also signed free agent Tevin Coleman, who had more than 1,000 yards from scrimmage (800 rushing) for the Falcons last year with nine combined touchdowns. Raheem Mostert also is listed on the unofficial depth chart.

"It's more of [determining] a pecking order," coach Kyle Shanahan told reporters earlier in the week (via "Just let it play out. I think we’ve got a pretty good feel for all the guys. We kind of have an idea what they can do ... we just want those guys repping. Right now, we don't really care what the play is. … We want them to compete and hopefully it sorts itself out. If it doesn’t, they’re going to make me have to make a very tough decision.”

The 49ers open the preseason Saturday at home against the Cowboys. San Francisco's regular-season opener is Sept. 8 against the Buccaneers in Tampa.