The Vikings plan to place Justin Jefferson on injured reserve Tuesday, according to a source with knowledge of Jefferson's injury. The star receiver sustained a right hamstring injury in the fourth quarter of Sunday's game against the Chiefs and will be out at least four games.

Jefferson's injury is the latest setback in a Vikings season that's started disastrously. The reigning NFL Offensive Player of the Year was injured in the fourth quarter of the team's 27-20 loss to the Chiefs on Sunday, when he slipped on the U.S. Bank Stadium turf and came up limping after his route on a throw to K.J. Osborn. He watched the rest of the game on the sideline with a towel around his neck; coach Kevin O'Connell said Monday that Jefferson was trying to find a way to get back into the game, but the team made the decision to rule him out.

Jefferson has never missed a game in his career because of injury. Despite teams devoting outsize attention to the wide receiver in the Vikings' first five games, he'd caught 36 passes for 571 yards and three touchdowns. With the receiver out, the Vikings will likely turn to first-round pick Jordan Addison, who led the team with six catches for 64 yards and a touchdown on Sunday against the Chiefs.

Addison played a career-high 54 snaps on Sunday, with Jefferson missing the team's final 20 plays after the injury. Afterward, quarterback Kirk Cousins said the receiver was "the real deal," adding, "We hit on that draft pick.

"When Justin goes down — which is tough; he's a special player — there's a lot of confidence that K.J. [Osborn] and Jordan and Brandon Powell and our tight ends and our backs can really fill that gap," Cousins said Sunday.

O'Connell did not offer a timetable for Jefferson's return during his Monday news conference, saying the team and receiver would likely seek multiple opinions on the receiver's injury. He did say the Vikings would take the long view on Jefferson's injury, adding, "We're going to have to medically make a good decision and help almost protect him from himself a little bit in a way where we have to take care of him and get him back to 100 percent."

The earliest Jefferson could return would be for the team's Nov. 12 game against the Saints, though the course of the Vikings' season could dictate how his return will play out.

The team fell to 1-4 after falling to the Chiefs, and will play three road games in the four weeks Jefferson is scheduled to miss, with the first of two NFC North road games coming this weekend against the Bears. The Vikings' only home game in that stretch is a Monday night matchup against the undefeated 49ers on Oct. 23. If the Vikings fall further back in the playoff race before the Oct. 31 trade deadline, they could look toward the future by dealing veterans who will be free agents after the season, like Osborn or pass rusher Danielle Hunter. Quarterback Kirk Cousins is also scheduled to be a free agent after the year, though he has a no-trade clause that would allow him to prevent any deal he did not approve.

Jefferson and the Vikings talked about a long-term deal for the wide receiver through the offseason, but talks stopped the day before the regular-season opener on Sept. 10 with the sides unable to come to a deal.

The receiver participated in all of training camp without a new deal and was named a team captain for the first time. He has said he would not let his contract status affect his approach to the season. "At the end of the day, all I can do is play football," he said after the Vikings' loss to the Buccaneers on Sept. 10. "That's what I continue to do. I know my team. My team doesn't care about the contract and I don't either. I just want to be here for my teammates, play for my teammates, and of course, get these wins." If the Vikings fall further behind in the NFC playoff race by the time Jefferson is slated to return, however, both the team and Jefferson's camp could deem it wise not to rush him back.

His injury came on the same day Chiefs tight end Travis Kelce sprained his ankle while slipping on U.S. Bank Stadium's playing surface, one of just three left in the NFL with a slit-film turf playing surface (the others are Cincinnati and Indianapolis). Last November, the NFL Players Association called for a ban on slit-film fields after Packers pass rusher Rashan Gary tore his ACL on the surface at Detroit's Ford Field.

Before the 2023 season, Ford Field shifted to a monofilament playing surface, which is considered to be closer to a grass field than other artificial surfaces. The U.S. Bank Stadium playing surface is scheduled to be replaced in 2024.