In case anyone thought otherwise, Vikings running back Adrian Peterson is still hellbent on starting and playing a significant role when the Vikings open the season against the Jacksonville Jaguars four months from today.

"I would be very surprised [if he doesn't play in the season opener]," said Peterson, who tore the anterior cruciate and medial collateral ligaments in his left knee in the Vikings' Christmas eve win at Washington. "I've been ahead of schedule since Day 1. ... From Square 1, I've been ahead of the curve. So me, personally, that's the goal. I set my expectations high and my goals high. So that first game against Jacksonville, I plan on being back. So it's important. I'll be disappointed if I'm not."

Vikings head athletic trainer Eric Sugarman and the team are optimistic but taking more of a cautious wait-and-see approach.

The Vikings felt strongly enough about Peterson's progress in the 19 weeks since his Jan. 30 surgery to allow the media to observe a workout today. About 40 reporters were there, including Hall of Famer and current NFL Network analyst Michael Irvin.

Peterson worked out in the field house for 15 minutes. He did some lateral work, fielding a soccer ball that Sugarman would roll to him. He also did some light cutting as he ran around a circle set up by Sugarman. He also sprinted the width of the field four times without his knee brace and did eight standing box jumps to a box that was about three feet high.

Sugarman said Peterson just cleared the important 18-week barrier and has reached a point where he can start cutting without fear of re-injury.

"He's to the point now where he's really safe to do just just about anything," Sugarman said. "We gradually ramp him up to functional activity and when we get to the point where he is comfortable and has normal strength back to the other side or better than the other side and can function as he needs to, then we can make that decision" on when he can return to football activities.

Sugarman said Peterson has been a good patient and is ahead of schedule. But he's not setting any goals for Peterson's return. That's OK. Peterson has Week 1 and he doesn't care what anyone says.

"I'm set on what my mindset it," he said. "People can say what they want to say. I got my goals. My whole life I've been setting my goals and pushing forward and I've been successful in doing that. I've been smart. Don't get me wrong. I've been smart about the process.

Asked where he gets this determined mentality, Peterson said, "That's just the way I'm wired. I've been this way since I was young, since I started playing this game at age 7. I always wanted to be the best in whatever I did -- whatever sprints, lifting, whatever. Sixteen years, 17 years of that, it becomes part of you. It's just instilled in me. It's just the way I am."