"My weight didn't allow me to do some of the things I wanted to do, and at the same time, I wasn't mentally dialed into the game," Peterson said. "Being overweight and not able to fall back on that athletic ability, it was like, 'Damn.' You really have to know what these (offenses) are doing, because someday I'm going to get old, someday I'm not going to be as fast as I was or as dynamic an athlete as I was in previous years."

Peterson got his symptoms under control by the end of the 2014 season, and as the weight vanished, the elite speed and change of direction returned.

The trick moving forward was mastering the mental approach, and the brush with mediocrity kicked Peterson's urgency into high gear. Last summer, he picked the brains of former NFL cornerbacks Deion Sanders, Bryant McFadden and Rod Hood to increase his knowledge base.

"I was always athletic," Peterson said. "I was always physically gifted. It was time for me to put the classroom work onto the field, as far as, now I'm not out there guessing routes; now I'm watching more film; now I'm understanding how teams are attacking me; now I know what's going to come, versus guessing at what's going to come."

McFadden, a two-time Super Bowl winner with the Steelers and a former Cardinal, told Peterson to focus on the nuances of the position. He used film of standout cornerbacks Darrelle Revis and Asante Samuel as a guide.

"When players come into the league with his talent and skillset, they overlook the mental game because they can be in a bad position and still make plays," McFadden said. "But you can only do that for a short time. Offensive coordinators watch film and they can attack you.

"It's easy for a guy as athletic as Pat to forget the little things, because he's thinking 'This is easy.' But expectations get higher the more success you have. He just needed to hone in on a couple things."

In 2015, the athletic freak added mental acuity, and it resulted in the best season of Peterson's career.

He drew the assignment of the opponent's No. 1 receiver every game, facing Calvin Johnson, Antonio Brown and A.J. Green, among others. Despite the supreme talent across from him, Peterson didn't allow more than four catches in a game all year and gave up more than 50 yards just once, per Pro Football Focus.

Peterson was named to the Associated Press' All-Pro team – Norman was the only other cornerback who received the honor – and to another Pro Bowl that, this time, was well deserved.