The toughest guy to cover on the Patriots might not be the man they call Gronk, the one who spikes footballs hard during the season and apparently slams shot glasses even harder in the offseason.

Yes, Patriots tight end Rob Gronkowski, who is back in the lineup after last year's ACL injury, will be a major threat to the Vikings defense. His sheer size and strength, in addition to respectable speed and a punishing style of play, have made him arguably the best all-around tight end in the league.

But Patriots running back Shane Vereen poses a potentially tougher challenge for the Vikings. He is New England's answer to Darren Sproles, and the Vikings might not have a linebacker or safety capable of keeping up with him, especially if the Patriots go with a spread passing attack Sunday.

Vereen, now in his fourth season, has shown a knack for being able to get open whether he starts out in the backfield or lines up at receiver. He had 47 catches for 427 yards and three touchdowns in eight games last season, though he had just five for 35 against the Dolphins last weekend.

"He went out last week [against the Dolphins] and you could see they've really got him running a lot of routes — wheel routes and option routes and those kind of things," defensive coordinator George Edwards said. "You can just tell they're very comfortable with him in their package and getting him out in space and getting him against 'backers and trying to get him one on one."

Vereen averaged 2.14 yards per route run last season, second among running backs to only Sproles. Only 11 qualifying wide receivers averaged more yards per route run than Vereen.

The Patriots use Vereen, who is capable of running many of the outside routes NFL wide receivers typically run, to create matchups in the passing game. If defenses cover him with a linebacker or safety, the Patriots try to exploit that mismatch. Or if they put Vereen out wide and a cornerback lines up across from him, quarterback Tom Brady knows to look for a favorable matchup elsewhere.

"He's an excellent back out of the backfield," Edwards said "He has good hands. He runs good routes. He's got the speed to take you vertical. His option routes and things, he does all the little nuances that you would want out of a back as far as leverage and coverage and being able to beat it. It looks like Brady has all the confidence in the world to throw him the ball."

While Vereen typically only gets five to seven carries as a runner — he has averaged 4.3 yards per carry in his career — he is a key player for their offense, especially when the Patriots go no-huddle.

"He's a guy that can do it all," safety Harrison Smith said. "So you have to keep your eye on him."

It will be interesting to see how the Vikings respond when the Patriots put Vereen and Gronkowski on the field together. Rookie outside linebacker Anthony Barr, who has the size and speed to physically man up with Gronkowski, may take on that challenge when the Vikings use man coverage concepts. But who covers Vereen? Outside linebacker Chad Greenway? A safety such as Smith?

"I trust in Coach Zimmer's scheme that he has put together," outside linebacker Gerald Hodges said. "I think he has us well prepared — we're not finished getting prepared yet, but we're well on our way — and he knows offenses in and out. As long as we pay attention to detail, I think we'll be fine."