Erin Henderson hasn't practiced this week as the Minnesota Vikings have inserted Marvin Mitchell onto the first-team defense as the team gears up for Sunday's game against the San Francisco 49ers. There's no telling when Henderson will return from injury, however, because the Vikings aren't sure when it actually happened.
Henderson left last weekend's game with an apparent elbow injury, but there was no talk of a concussion suffered against the Indianapolis Colts until Wednesday's practice, according to head coach Leslie Frazier.
"Wednesday he came out to practice and just didn't feel right," said Frazier of Henderson, who leads the Vikings with 22 tackles and two sacks.
It's a tough injury for the Vikings considering Mitchell hasn't played this year due to injuries of his own, but the fact that Henderson may have played with a concussion is an even bigger cause for concern.
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