Only four seconds remained last Sunday when Blair Walsh trotted onto Mall of America Field for the first high-pressure kick of his NFL career.

The Vikings trailed Jacksonville 23-20 after surrendering a demoralizing late touchdown.

Walsh faced a 55-yard game-tying kick, longer than all but one of the field goals he made during his four years at Georgia. The adrenaline and anxiety were quickly elevating.

Until Adrian Peterson approached on his way off the field, offering an encouraging bop to Walsh's head, a thump so forceful it actually turned the kicker's helmet a few inches.

Walsh's first thought: "Wow, that's ridiculous."

The rookie's startled laugh broke the tension. He made the kick with ease.

"I don't think Adrian knows how strong he is," Walsh said.

Yep, sources have confirmed it. Peterson continues redefining ridiculous. And nope, he doesn't seem to know his own strength.

A week ago we were wondering whether he would even play against the Jaguars, just a little more than eight months after he underwent major surgery on his left knee. Now, with the Vikings in Indianapolis, we're wondering whether Peterson is already set to take on a full workload.

Maybe a 22-, 23-carry day?

Seems hopeful. But don't rule anything out.

Not with the way Peterson ran a week ago, using his confidence and self-professed faith to run right past the hesitation that should be slowing him down right now.

Now the question must be asked: Will Peterson's rapid recuperation be a source of inspiration for a team trying to prove it can accomplish more than a huge legion of outside doubters believe?

Or will Peterson's extraordinary progress skew the realistic view for how quickly dramatic upturns can occur?

After all, for months Vikings fans have been lectured to have patience with this young squad, reminded that after a season as frustrating and failure-filled as last year's, remarkable recoveries just don't happen in the blink of an eye.

Except when they do.

Last week, Peterson delivered 17 carries for 84 yards with two touchdowns. And had receiver Stephen Burton held his block just a second longer on Peterson's longest run of the day, a 20-yarder in overtime, the chaos at the Metrodome may have culminated with a 62-yard game-ending touchdown run.

"It was real close," Peterson said.

Which means Peterson was real close to having himself a 130-yard, three-TD day. In his first game back after ACL surgery.

Colts coach Chuck Pagano has watched the film of the Vikings' opener and sees little difference between the Peterson of last week and the one who chewed him up for 166 yards from scrimmage in 2009 when Pagano was defensive coordinator in Baltimore.

"He's a superhuman guy," Pagano said. "Just a rare, rare, rare talent."

Pagano was particularly impressed with Peterson's first touchdown run, a 3-yarder that required an instinctive and sharp cut back left.

On the Vikings' next drive, Peterson scored again, launching himself into the end zone from the 3, then quickly doing a back somersault to pop to his feet.

Yes, Peterson experienced some minor soreness and tightness in his knee after the game. But, he said, that was to be expected. He also believes he's only operating at about 95 percent right now.

So just what is missing in that final 5 percent?

"Just being more explosive with my strength," Peterson said. "It doesn't sound like much from the outside looking in. But I know my game and I know where I want to be. And it's going to be huge once I get to 100 percent. Like night and day. Seriously."

Most refreshing? With every reason to be boastful, Peterson hasn't launched a vain "Look at me" campaign. Instead, he's simply asked outsiders to understand the unwavering self-belief he's used in his comeback.

"I had my vision, I knew what I wanted to do, and that's all that matters," he said.

Ridiculous. Guy doesn't know his own strength.

Dan Wiederer • dan.wiederer@startribune.com