Minnsota Vikings rookie LB Audie Cole has made a strong case to make the 53-man roster -- getting a sack against the 49ers and returning two late-game interceptions into touchdowns against the Bills.

“Well, it definitely helps when a guy makes plays in a game,” said coach Leslie Frazier on Sunday. “You don’t want to discount that. That means something whether it is the first unit or third unit. It was good to see him step up and make some key plays when he had the opportunity to. Others guys at times will be in those situations and don’t make those plays. So you like it when a guy does.”

But Frazier said the coaches have to weigh everything when making roster decisions. Cole came in with a reputation for being a bit slow for a LB. But he's tall and Frazier says he can cover ground quickly. His length and smarts helped him Friday night.

“He has good instincts and he has good anticipation," Frazier said. "He’s a smart football player and that can offset a guy who doesn’t have blazing speed. But you take that all into account. We have a few weeks more in camp. We will look at his entire body of work as we are tying to make a decision on what’s best for our team.”

More secure at safety: Coach Frazier liked what he saw in his safeties Friday and said that the same duo -- Mistral Raymond and Harrison Smith -- should start Friday against the Chargers.

“That’s the approach we are going to take,” said Frazier. “(Mistral) did a good job in the ballgame on Friday night, and we want to look at that tandem again and see how they progress. We will still work Jamarca (Sanford) in there, but I think, as we speak, we want to go with those two to begin with.”

Phasing out Simpson: WR Jerome Simpson had a nice game against the Bills, and the Vikings may have a seen enough to start cutting back his first-string reps in preparation for Simpson’s suspension for the first-three regular-season games.

“We’re going to have him in there (against the Chargers), but we’re going to have to take a look at some guys who are maybe going to be playing in that first game,” said Frazier. “We’re definitely going to approach it like the first ball game of the season and we wouldn’t have Jerome for that first game.”

Sad news: The only player not at practice Sunday afternoon was FB Matt Asiata, who was on leave after a death in his family. 

Injury update: TE Kyle Rudolph and CB Chris Cook were experiencing concussion-like symptoms after getting hit in Friday’s game. They were at Sunday’s practice but were not participating.

“Chris and Kyle are both still under observation,” said Frazier. “They are both being evaluated for the concussion symptoms. We will learn more about both of them (Monday.) Up to now, everything (regarding concussion-test protocol) has gone smoothly.”

LB Solomon Elimimian, who sat out the Bills game with a strained hamstring, had an MRI on it that came back negative. “We will see how he does day-to-day,” said Frazier.

RG Geoff Schwartz, who is out following sports hernia surgery, was seen jogging around the practice field. He’s projected to be out 3-to-6 weeks.

TE John Carlson has been out for the past two weeks with a sprained MCL in his knee, and being new to the offense, it's important that he returns soon.

“John Carlson is still making progress,” said Frazier. “We’re going to see how he does day-to-day and make a determination whether or not we want to try to play him in this ball game or not.”

Coach Frazier said he expects to get DB Robert Blanton (hamstring) back this week. Blanton was practicing on Sunday and did well, according toFrazier.

DT Letroy Guion should be able to practice this week, according to Frazier, and the team will make a determination about whether they want to play him against San Diego. The same goes for OL DeMarcus Love, who has been out with a shoulder injury.

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