Vikings LB Erin Henderson, who has been recovering from a concussion the past two weeks, may be returning to the lineup just in time after his replacement, Marvin Mitchell, left practice with a calf injury Thursday. (US Presswire)

Vikings LB Erin Henderson, who has been suffering with a concussion the past two weeks, was able to go through an entire practice on Thursday, and it could be just in time. LB Marvin Mitchell, who took his place in the lineup, left practice with a strained calf.
"Marvin ended up stretching his calf,” coach Leslie Frazier said. “So we had to do an MRI to make sure everything is fine. We sent him in to get that done.”
For the past two games, Mitchell filled in for Henderson in base defense, and then MLB Jasper Brinkley stayed in the game in nickel situations -- a position that Henderson had before the injury. And now Henderson won’t get that role back immediately upon his return.
“We made a decision and we are going to let Jasper stay in that role for now,” said Frazier.  “[We’ll] let Erin continue to work his way back [into the lineup] and make a decision down the road if he is going to end up back in the position.”
Frazier said Brinkley has filled in well for Henderson, and, for the time being, this decision definitely backs that up.
Injury updates: DE Jared Allen (groin) did not practice on Thursday. He was seen running on the side and then went indoors for treatment.
“Jared is still down,” said Frazier. “We are hoping to have him back at practice [on Friday]. I think he will be fine for Sunday. But we just want to make sure to be a little cautious because he has been sore. He will get some work [Friday].”
QB Christian Ponder was limited on Wednesday with soreness in his right knee, but Frazier said he was much better on Thursday. Ponder apparently hurt his knee on Sunday when Lions DE Kyle Vanden Bosch hit him.
“It didn’t really bother him on Monday,” said Frazier. “But it was really sore on Wednesday. He was much better [Thursday]--he didn’t have any inhibitions.”
WR Michael Jenkins (ribs), CB Antoine Winfield (knee), CB Marcus Sherels (quadriceps) and LG Charlie Johnson (lower back) all were limited in practice. S Andrew Sendejo (ankle) and S Mistral Raymond (ankle) did not participate.

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