In this week's tip from AskMadden.com, we go over the importance of having a big-play threat at the receiver position.

The Minnesota Vikings are off to an amazing start this year, posting a 7-1 record. Many people will say that their success can be attributed to Brett Favre or Adrian Peterson. Yes and yes. But no and no.

Rookie sensation Percy Harvin and veteran receiver Bernard Berrian are the key factors to the explosive and unstoppable Vikings offense this year. Both of these receivers possess track-star speed -- Harvin and Berrian each have 97 speed -- that forces defenses to drop safeties into deep coverage on almost every play. So what these threats do is open up the rest of the field for Brett Favre and Peterson to do their jobs even more effectively.

As shown in our video below, if you play against man coverage and there is no safety help, you can make a pass to either one of these burners for a quick six. If you notice the secondary is dropping back to help out on the pass, then utilizing Peterson on halfback draw plays can be extremely effective. With the balance and explosiveness that this offense has from top to bottom, it's no wonder the Vikings are right in the mix for Super Bowl contention.