EDEN PRAIRIE, Minn. -- I joined a number of reporters Wednesday afternoon at the Minnesota Vikings' practice facility, where tailback Adrian Petersonwas scheduled to discuss the rehabilitation of his surgically-repaired left knee. On cue, Peterson popped his head through the door. With athletic trainer Eric Sugarman at his side, Peterson motioned for us to join him at the far end of the practice field.

For the next 15 minutes, Peterson demonstrated the extent of his progress by running two sets of sideline-to-sideline sprints. He performed a series of box jumps, moved laterally to catch a rolling soccer ball and ran tight circles around a wide hula hoop.

The scene was impressive for a player 19 weeks removed from tearing two ligaments in his knee. As he caught his breath afterwards, Peterson reiterated his intent to be ready for the Vikings' Week 1 game against the Jacksonville Jaguars, by far the early side of the typical range for injuries as significant as his.

"People can say what they want to say," he said. "I've got my goals."

I felt conflicted watching Peterson work out and listening to his optimism. Part of me admired his intense desire to return ahead of schedule. The other part kept flashing back to the end of "Fargo."

And for what?

If it wasn't clear before, it should be obvious now. The Vikings have launched a full-scale roster rebuild that should better position them for the long-term but will almost certainly sacrifice the short-term to do it. The latest evidence was this week's decision to jettison still-reliable place-kicker Ryan Longwell for rookie Blair Walsh, perhaps the most extreme example of the team's systematic effort to make its roster younger.

A cynic might say the Vikings know they won't compete for an NFC North title in 2012, making this season as good of a time as any to break in a new place-kicker. Here's what general manager Rick Spielman said Wednesday:

"I think our emphasis has always been trying to get our team better, get it younger, and that's the direction we kind of went. It just fits in with everything else we’re kind of honed in on this offseason."

It's hard to argue with that approach after a 9-23 record over the past two seasons. But as we first discussed last fall, it threatens to nullify the prime of one of the NFL's best players.

Peterson is 27 and has taken the pounding of five professional seasons. By the standards of NFL running backs, at least, the clock on his career is already ticking. It's more than reasonable to wonder what type of performer he will be when the Vikings see the fruit of their rebuilding project.

I asked Peterson what he thought of the Vikings' offseason approach, and he focused mostly on praising Spielman's draft. Peterson also admitted that "the biggest part of my motivation" to return in Week 1 is because "I know how much I mean to this organization." He added: "I want to be out there helping my team and organization accomplish the ultimate goal."

Even with Peterson in the starting lineup, the Vikings figure to have new starters at 11 positions in 2012 in addition to an unproven second-year quarterback in Christian Ponder. In all likelihood, it will be a year measured by progress, not playoff contention.

I'm not going to suggest the Vikings should hold Peterson out of the lineup once he's medically cleared. But in the big picture, there seems to be every reason to take it as slow as possible. If Peterson can avoid some wear and tear during a rebuilding season, wouldn't that help the Vikings in the long-term?

That's a cold and calculated analysis that isn't likely to apply in this case. Neither the Vikings nor Peterson should time his rehabilitation progress based on the projected competitiveness of the team. NFL teams are expected to compete with all available resources at all times. It's not for Peterson to "save" himself for future seasons. The timing is what it is.

The best thing Peterson can do in the short-term is help this team squeeze out a few more victories than it appears capable of while imposing his fanatical work ethic on others. He seems to understand that as well. During rehabilitation a few weeks ago, Peterson noticed some teammates running sprints. Sugarman gave him permission to join them. He wiped out the field.

"Those guys got an understanding of 'Hey, he's really pushing hard to get back out to a level better than he played at before' and it was even more motivation for those guys," Peterson said. "It was like, 'Hey he's out here four months and he's beating us.' Maybe we need to do something different."

Knowing Adrian Peterson, he'll do everything he can to will the Vikings to more success than expected in 2012. It's reasonable to question whether it will be enough, and to wonder how long it will take the rest of this roster to catch up. Will Adrian Peterson be this generation's Barry Sanders? Is he a Hall of Fame player whose career window doesn't match up with his team's window for winning? That's what it feels like at the moment.