The Facts: Whether new HC Chip Kelly's fast-paced attack would work as well at the professional level as it did in college was one of the most intriguing questions heading into this season. However, NFL rules likely will force Kelly to make adjustments. "We have to make sure teams understand that they don't control the tempo, our officials do," NFL vice president of officiating Dean Blandino told The Wall Street Journal. "We're going through our normal ball mechanics, we aren't going to rush [unless] it's in the two minute drill."

Diehards Line:Under Kelly, Oregon ran 1,077 plays in just 13 games last season (82.8 per game), according to ESPN Stats & Information. That would have ranked seventh (just two total plays behind the Eagles' 1,079) in the NFL's 16-game schedule this season. The New England Patriots led the NFL with 1,191 plays this season (74.4 per game). Kelly wants to run a play every 12 seconds, so he gets the Eagles ready for it in practice, even having assistants calling in plays via elaborate hand signals from the sidelines. The Eagles run a ton of plays, move around quickly and don't spend much time waiting, doing nothing. But that could change come game days. Blandino told the newspaper that he has told each team's coaching staff, however, that teams will not be able to snap the ball until a referee gives the signal. NFL rules also state that a defense must be allowed to make substitutes if the offense substitutes its own players, no matter how quickly the offense makes it changes. Blandino told The Journal that the referee will stand over the ball to ensure that it is not snapped before the defense is set.