MINNEAPOLIS -- The Minnesota Vikings are 4-0 in part because of how quickly Sam Bradford -- traded to the Vikings eight days before the start of the regular season -- has been able to establish fluency in the team's offensive system. But a change to the way the Vikings call plays has helped, too.
In the time-honored Air Coryell system that Vikings offensive coordinator Norv Turner has used during his 32 seasons in the NFL, different routes are given numbers from 0 to 9 (a "7" route is a corner route, an "8" route is a post route, a "9" route is a go route, etc.