Whether or not Chip Kelly's offense becomes successful in Philadelphia is uncertain. What is certain: It'll become a headache for defensive coaches.

Under Kelly, the Eagles' offense will likely be, at the least, an adaptation of what he ran at Oregon. It's similar to the Redskins, in that he uses the zone read, though Kelly often runs it differently. The unique part is the speed at which Kelly wants to run his offense.

"It's all the things they have the capability of doing, and then you add the fact that they're going 100 miles an hour and you really don't have a whole lot of time to do a whole lot of thinking," said former Ohio State University defensive coordinator Jim Heacock, whose defense held the Ducks' attack to 17 points and 260 yards in the 2010 Rose Bowl.

One way they prepared for the speed: After one offense finished a play in practice, another one would line up while the defense subbed players and got in position. That's easier to do in college with more players available. Another trick: The offense would line up while the defense had its back turned to the ball. At the coaches command, the defense would turn around, receive the defensive call and then react.

A defense must be creative in changing looks, and changing who the quarterback must read to determine whether to hand off or keep the ball. But, in the end, as Heacock said in John KeimSSRqs Redskins Report email newsletter, "A lot of the hurry-up in defending ... is just poise and keeping it under control."

- John Keim