MANKATO – Every defensive back remembers his welcome-to-the-NFL moment, that split second when a professional defensive back receives tangible evidence that he's no longer defending unpaid college kids.

"Brett Favre threw a no-look slant on me in practice my rookie year," said Vikings cornerback Chris Cook, a second-round draft pick in 2010. "He looked this way and threw that way. No-look. And still completed it in stride. Never seen that one before."

The Vikings secondary is about to get an eyeful of elite NFL quarterbacks. In fact, if the Vikings' 2013 schedule were a weather report, Paul Douglas would be interrupting regularly scheduled programming to advise Chris Cook, Josh Robinson, Xavier Rhodes, Jamarca Sanford and Harrison Smith to spend the next four months hiding in their basements.

"I don't want to leave anybody out," said Smith, the starting safety. "We got Eli Manning, all the guys in the division, [Tony] Romo, RGIII, Cam Newton, Russell Wilson. Did I forget anybody?"

Only Joe Flacco, the reigning Super Bowl MVP. And Ben Roethlisberger, a two-time Super Bowl champion.

Vikings coach Leslie Frazier put the kibosh on receiver Greg Jennings talking about the size of Aaron Rodgers' ego. But he probably won't mind his top five defensive backs talking about the size of Rodgers' Hall of Fame-bound talent.

Three of those defensive backs — Cook, Smith and Sanford, the starting strong safety — said Rodgers was the greatest quarterback they have ever faced in their careers. One of them — Rhodes, a rookie from Florida State — picked former North Carolina State quarterback Mike Glennon because, well, he's never had the opportunity to compare Glennon's "great back-shoulder throws" to Rodgers' unstoppable precise back-shoulder throws.

The other defensive back — Robinson, who should win the slot corner position in the oft-used nickel defense — labored over the question before punting.

"I'd say RGIII … no, wait," said Robinson, a second-year pro. "Andrew Luck? I don't know. Russell Wilson? Man, I have no idea. They're all so good and so consistent."

So what makes a guy like Rodgers so great?

"It's their preparation," Cook said. "And their confidence to trust their preparation. They make a decision and go with it. Bang, right now."

Playing Rodgers twice a year doesn't make it any easier.

"He knows the ins and outs of our defense," Sanford said. "Sometimes, he knows what you're going to do even before he snaps the ball. And he can run, too. You don't think he's fast until he gets going."

"And that mobility keeps plays alive long enough for guys to get open," Smith added. "That's tough, especially if you don't hold your [disguise] long enough because he not only had a great understanding of what he's doing, he also has a leg up because he has a great understanding of what we're doing."

So what's a defense to do when the other guy knows your next step, has good mobility and can knock an amoeba off a flea's back at 40 paces?

"Sometimes, a guy like Rodgers and Favre, they can beat you even in your best coverage," Sanford said. "But sometimes if you have a good disguise, they fool themselves. They see something that's really not there. You got to give them something to look at that's really not there to see."

And you thought it was easy playing defensive back in the NFL.

"These guys will throw no-look slants, no-look fades, no-look comebacks," Robinson said. "They just know where their receivers are going to be. They throw it and they just expect the receiver to be there. And the good teams with the great quarterbacks, the receiver is always there.

"And sometimes," Robinson added, "you see all this as a cornerback and it's like, 'Really?' I can't believe the quarterback had that much confidence to make that throw, just expecting the receiver would be at that exact spot at that exact moment. But that's just the nature of the beast in the NFL."

Mark Craig • mcraig@startribune.com