It’s official: The Minnesota Vikings will be without star wide receiver Justin Jefferson for at least a month.

Wednesday, the team officially put Jefferson and backup quarterback Nick Mullens on injured reserve, meaning they’ll miss at least the next four games. Those games are against the Bears, 49ers, Packers and Falcons, with only the 49ers game in Minnesota.

Jefferson hurt his hamstring late in Sunday’s loss to the Kansas City Chiefs while Mullens has been dealing with a back injury that forced him to be inactive for the Chiefs game.

To fill their roster spots, the Vikings signed wide receivers Trishton Jackson and N’Keal Harry from the practice squad. Both players have been with the team since training camp.

Additionally, to fill out their practice squad, the Vikings signed wide receiver Dan Chisena, quarterback Sean Mannion and tight end Troy Fumagalli. Chisena was a special teams player with the Vikings from 2020-22, appearing in 27 games, while Mannion played in four games for Minnesota from 2019-21. It comes a day after the Vikings released former Gophers quarterback Tanner Morgan from the practice squad.

The club also designated running back Kene Nwangwu to return to practice, starting his 21-day window to return to practice. He’s been on injured reserve since the start of the season.

The Vikings sit at 1-4 and face Chicago, which is also 1-4, on Sunday in Chicago.