Coach Kevin O'Connell said after Sunday's 27-20 loss to Kansas City that it's too early to know how the hamstring injury that Jefferson suffered in the contest will affect his availability.
Jefferson wasn't able to return after hurting his hamstring early in the fourth quarter, ending Week 5 with three catches on six targets for 28 yards. He had a visible limp as he made his way to the sideline, where he visited the medical tent, and he was merely a spectator afterward. If Jefferson is limited or unavailable for next Sunday's road game against the Bears, the Vikings may again have to lean heavily on rookie Jordan Addison, who led the team with a 6-64-1 line on nine targets against Kansas City.