MANKATO – A catalog of new plays filled Stefon Diggs' brain on the first day of offseason workouts. Everything was new and different, and he wanted to make sure he had a grasp of his responsibilities.

So he grabbed his helmet and went to the field by himself.

It was late in the evening on the Vikings' first day of OTAs at Winter Park. Most of the players already had gone home for the day.

A team employee looked out at the practice field and noticed a lone figure.

It was Diggs, a rookie, running different pass routes that he had learned earlier that day.

"It was my first time being in this offense and seeing certain plays," Diggs said Thursday, "so I wanted to be out there on the field and get a feel for it."

Diggs

Word of Diggs' impromptu session filtered back to Vikings wide receiver coach George Stewart, who never asked his new pupil about it but nonetheless expects that kind of focus from his fifth-round draft pick.

"I want him to be a gym rat," Stewart said.

That's a salient point worth examining when evaluating Diggs' first training camp — more than all the hype and glowing reports about his flashy catches in practice.

Diggs himself shrugs off any praise involving a buzz he's created the first two weeks of camp.

"I haven't done anything yet," he said. "This is practice and as far as making plays in practice, they don't count for anything."

Refreshing, isn't it?

Internally, the excitement Vikings officials feel about Diggs' potential is palpable. He's fast and elusive and has made nice catches in practice. He looks the part.

However, a cautionary tale about setting measured expectations exists on the same team at the same position. Cordarrelle Patterson's regression serves as a reminder that talent alone means nothing without a proper foundation.

That's why Diggs is sticking to veterans like barnacle, absorbing as much information as possible. Listen and learn has become his camp motto.

"I'm just trying to serve as a sponge right now," he said. "I've got a lot of work to do."

His own path to this point offers proof that nothing is guaranteed. Diggs was rated a top-10 national recruit in high school. All the powerhouse college programs wanted him. He elected to stay home and attend Maryland.

Diggs encountered a few significant injuries and inconsistent quarterback play in three so-so seasons. He suffered a lacerated kidney against Penn State last season on a hit by a linebacker while lunging for the goal line.

Diggs finished the game and didn't learn the seriousness of the injury until he went to the bathroom after the game.

"I said, 'Ah, something is wrong,' " he said.

Diggs opted to forgo his senior season, and the Vikings were delighted to get him in the fifth round. He had an ally in Vikings quarterbacks coach Scott Turner, who recruited Diggs in high school as an assistant at the University of Pittsburgh.

Turner went to Stewart's office back in January and encouraged him to evaluate Diggs as a possible draft option.

Stewart raves about Diggs' athleticism, but Vikings coaches and players sound more impressed with the rookie's eagerness to learn the finer points of his craft.

"I love that he remembers his mistakes more than the good plays," quarterback Teddy Bridgewater said. "When you make a good play, everyone's going to pat you on your back and tell you how good you're doing. But to be able to process those bad plays and learn from them and then not make the same mistake twice, that's what I love about him."

Diggs said he wants to do things "by the book." For instance, if his route calls for him to run 7 yards, run 7 yards on the dot.

"Not 7½," he said.

"I really need to grasp the offense," Diggs said. "I'm trying to be as smart as I can [since] I'm new to the league. I'm trying to learn all the information I can and do it the right way."