MANKATO - Adrian Peterson walks out of the locker room door and pandemonium ensues.

"ADRIAN! ADRIAN!"

If there is any doubt about who the most popular Vikings player is, the answer comes through loud and clear every time Peterson shows his face at training camp.

A year ago, Peterson was a first-round draft pick with plenty of promise. Now he is the team's resident rock star. He reached that status after a historic debut season earned him rookie of the year honors and brought a windfall of business and marketing opportunities this offseason.

Peterson set the bar high for himself. But judging by his performance in camp so far and in the eyes of his coaches and teammates, Peterson has improved as a player and become more comfortable as a team leader.

"I feel totally different," Peterson said.

Peterson said he is more comfortable with the offense and feels like a more complete back, capable of playing on every down. He spent the offseason gaining a better understanding of blocking schemes and protections. He's also worked on being a more patient runner, allowing his linemen to set up their blocks rather than always looking for the big play.

"He's stepping up his game professionally," running backs coach Eric Bieniemy said. "He's taking his playbook home. Things are starting to make a little bit more sense to him. I think that's the giant step he's taking forward."

His life also has changed off the field. Endorsements rolled in after his rookie season. People wanted more of his time. Turn on the TV and you're likely to see Peterson in a commercial.

Peterson seems to have a firm grasp of that side of the business, too. He said he's learned to manage his time and keep his life in balance, although team officials admit they still worry about him being pulled in too many directions.

Peterson remains gracious with his time with fans and media, which is not always the case with athletes who have ascended to superstar status.

"That's not my nature [to say no]," Peterson said. "I'm just trying to enjoy it while I'm playing because when I'm 50 years old and people don't know me, I'll be like, 'I kind of miss that.'"

Teammates say Peterson's skyrocketing celebrity has not affected his work ethic or attitude. They do find some of it surreal, though.

"I was at a movie and he came on doing a commercial ... with an astronaut suit," quarterback Tarvaris Jackson said. "It's crazy to see him on there because he is your teammate."

Setting the bar high It took all of about five minutes in the first training-camp practice for Peterson to make his presence felt on the field. He appeared to be in midseason form while others were still trying to find their legs.

"He looks better than he did last year," safety Darren Sharper said. "The guy is special. You have to come up with a better adjective than special. I've got to look in my thesaurus or dictionary to find one. He just has 'it'."

"That dude is just amazing," defensive tackle Pat Williams said. "There's nothing else to say. That's an amazing cat. I just be watching him, smiling."

Peterson is not bashful about his expectations. After rushing for an NFC-best 1,341 yards in 14 games, he stated on several occasions this offseason that he wants to reach the 2,000-yard mark this season. He has preferred to discuss team goals in camp but reiterated that 2,000 yards remains his personal goal.

"People want to make that the main focus and that's not the main focus at all," he said. "I have my individual goals but my main goal is to win the division and get to the Super Bowl. If along the way I get that, it happens. It's going to remain 2,000 every year but it's not my main focus."

Vikings coach Brad Childress said he appreciates the fact that Peterson has such high expectations for himself.

"He's a guy that sets outrageous goals and meets them, and that's fine with me because he's shown he can handle that," Childress said. "And he knows he's not going to sneak up on anybody."

Teams undoubtedly will script their game plans with Peterson in mind. But Peterson is confident he's elevated his game.

"There were some things I looked at [on film last season] and was like, 'Man, that was crazy,'" he said. "But there were definitely a lot of things I looked at and felt I could do a whole lot better."

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