Peterson shows he's maturing

Vikings running back coach Eric Bieniemy has been like a big brother to Adrian Peterson from the day the former Oklahoma star put on a NFL uniform, a bond that began when Peterson was in high school and Bieniemy tried to recruit the best running back in pro football for UCLA.

So the man to go to when trying to find out what makes Peterson tick is Bienemy.

In the Vikings' 24-10 victory over the Lions on Sunday, Peterson ran 23 times for 160 yards, including an 80-yard touchdown run, the longest of his career.

Bieniemy was asked why Peterson is off to his best start in his four NFL seasons.

"He's showing some signs of maturity. I know it's early in the season. I think he's finally starting to understand he can't do it on his own," Bieniemy said. "He's a very highly competitive, motivated player, and he wants to do it like he wants to do it right. But the main focus that he has to [have] is just being patient. Letting the game come to him and just being patient and allowing guys to work for him."

Bieniemy said he has been stressing that since Peterson's rookie season of 2007.

"I think more so than anything, it's just finally starting to catch on, and knock on wood when I say it," Bieniemy said. "It's only Game 3, we still have a lot of football left. We still just want to make sure we remain patient and we're playing hard.

Better protector One thing Peterson had to improve on was to protect the quarterback, something he didn't have to do very often before Chester Taylor signed with the Bears as a free agent over the offseason.

"He's doing a really good job; we're light years ahead of what we've been in the past three years," Bieniemy said. "It's always a work in progress. So has he improved? Yes. Is he where I want him to be? No. We've still got things that we need to work on, still got little things that we need to correct."

And it's been frequently documented that Peterson has had to protect the ball better, too. Peterson fumbled 20 times in his first three seasons, including six times last year. He has not fumbled this year.

"We don't like mentioning that word," Bieniemy said. "We're just going to make sure that we're doing a better job of just focusing on the ball."

Cook does good job One thing a coach doesn't want to see is a starter getting injured on the first snap of the game when his regular backup isn't even dressed.

So Ryan Cook, who was a center in college at New Mexico but has been used mainly at tackle and guard in his previous four seasons with the Vikings, was pressed into action. He hadn't worked with quarterback Brett Favre to any extent, and there were plenty wondering how the loss of Sullivan would effect the offense.

"He hadn't played [center] for a long time," offensive line coach Pat Morris said of Cook's lack of experience at center. "But we had him prepared for it because he had played some through training camp and he had played it in some games this preseason."

Morris said what makes Cook valuable is he can play all the offensive line positions: guard, tackle and center. Cook said he did play two or three plays in the Vikings' blowout victory at St. Louis and some in preseason, but this was by far the most he ever played center in the NFL.

"I've always had a certain comfortability level with playing center," Cook said. "Obviously I think having the reps in the preseason definitely helped me to be able to be prepared for today's appearance. I do take all the mental reps when the guys are up there doing it every day, so I think that definitely helped. And trying to be ready and be prepared, you never know the situation, like today, and obviously you've got to plan for it.

"... I thought we did fairly well. Obviously, I still have some things I need to work on, some different protection calls and other things. But it's a learning experience and we'll move on from there."

"We just tried to get him in the rotation earlier," defensive line coach Karl Dunbar said of Robison, who had three tackles Sunday, including a sack. "We only dressed three defensive ends because we dressed a whole bunch of DBs, so we had to get him in there. ... He played left end, he played right end, he played inside, so he's a utility man."

The Vikings have been doing a lot of substituting at the defensive tackle positions, too.

"We try to take Pat [Williams] off the field on certain situations where we didn't think they were going to run the ball," Dunbar said. "So we get Jimmy Kennedy on the field and Letroy Guion on the field.

"That's the plan, to try to keep them fresh during the year so in November and December, when we're getting ready to make the push, everybody will be healthy, hopefully."

Rookie makes debut Cornerback Chris Cook, the second-round draft choice, saw his first NFL action as a nickelback after being sidelined for the first two games because of a knee problem. He had four tackles and a pass defensed.

Cook said he wasn't nervous, but he was way too excited. "My hands were shaking, and I was just jumping around everywhere," he said. "I just couldn't wait to get going."

As for the future, he said: "I definitely feel as time goes on, I'm going to get better and better every day. ... I have such a good work ethic and I want to be mentioned among the greats, so I'll do whatever I can to be great."