There was a moment when Antoine Winfield knew the Vikings had something in rookie cornerback Josh Robinson.

It was the preseason, Vikings against San Diego, second quarter. On third-and-11, Charlie Whitehurst of the Chargers completed a pass to fullback Jacob Hester. Well before he got to the first-down marker, Robinson came up and hit Hester, hard.

"You could see he was not afraid of contact," Winfield said.

For the veteran cornerback, this is important. Everybody could see from the first minicamp that Robinson was every bit as fast as his reputation, which started to grow when he ran the fastest 40-yard time (4.33 seconds) in the pre-draft combine.

But wed that speed with a willingness to hit? Winfield's eyes light up.

"I love his toughness," Winfield said. "And here's another thing -- he's not afraid of the bright lights."

As it happened, Robinson jumped up after the play, then staggered. Winfield directed him to the sideline.

Turns out Robinson saw some bright lights on that hit. He had a concussion.

"Hey, now and then gunfighters get shot too," Vikings defensive backs coach Joe Woods said.

But Robinson had made a few believers as he headed off the field that night.

And last Sunday in the victory over Tennessee, Robinson started at cornerback in the base defense, with Winfield playing the slot in nickel. Robinson responded with seven tackles.

Learning process

Robinson played mostly man-to-man coverage at Central Florida, and it has been difficult to assimilate all the man and zone coverages the Vikings use.

"The toughest thing has been trying to grasp what they want done," said the third-round (66th overall) pick. "And executing that on a consistent basis."

There is also work to do on technique, though that speed gives the rookie some margin for error. Robinson had four solo tackles in his debut against Jacksonville and three more in Indiana. Against San Francisco, he showed both his speed and toughness. On the second-half kickoff, he ran down 49ers returner Kyle Williams for a TD-saving tackle, and San Francisco settled for a field goal. On defense, he had three tackles and his first career interception.

The man is not afraid of the bright lights.

"You always have that confidence in yourself that you belong here," Robinson said. "And that's something you drive off of, knowing you belong. It continues to grow each week."

Rookies stand out

Robinson is a part of what is turning out to be a very strong 2012 draft. Top picks Matt Kalil and Harrison Smith have started from Week 1 at left tackle and safety, respectively. Kicker Blair Walsh has shown leg strength and accuracy. Robinson's role is expanding.

"Everybody knew he was fast, everybody was raving about this speed," linebacker Jasper Brinkley said. "When he got here, I saw that speed, but I also saw he was put together pretty good. And that's good. We like to have 11 guys on the defense willing to hit people."

And he's willing to learn. Woods likes Robinson's combination of size (5-10, 199 pounds) and speed. But just as important are his confidence and eagerness. Both Woods and Winfield mentioned that Robinson doesn't talk much but that he sure does listen.

"He is wired in," Woods said. "He listens to me, to Antoine, and you can see him trying to take that onto the field."

Robinson is on the field more and more, gathering experience that will allow his style to catch up to his speed.

"Right now, he's relying on that athletic ability, that speed," Winfield said. "With that speed, nobody in this league will run by him. And when he starts playing the proper technique? Let's just say this guy has a long career ahead of him."