Chip Kelly and Michael Vick will unveil their offense, for real, tonight. (Matt Rourke / AP)

No one outside of the Philadelphia Eagles’ facility knows exactly what to expect from Chip Kelly’s offense tonight when the Eagles play the Washington Redskins at FedEx Field.

Oh, it will be fast. That’s a given. But how fast? “A lot faster than I thought,” quarterback Michael Vick, who will be running the offense, told ESPN’s Lisa Salters.

“It’s going to be up-tempo,” Vick said. “It’s going to be something like you’ve never seen before as far as timing and getting to the line and getting plays called. A lot of time [will be] left on the play clock and a lot of plays ran in the game.”

Just how fast is fast? “You may see the ball carrier hit the ground and, if you count to 10, we may be on the ball snap, snapping the ball again,” he said. “Within 10 seconds or maybe less.”

Unless game officials can’t keep up. They’ve had no problem with the New England Patriots, who fell nine plays short of breaking their 1994 their NFL record with 1,191 plays from scrimmage last season. But on-the-field officials control the tempo, a fact that the NFL took pains to remind teams of over the summer. Tonight, sometime after 7 p.m. EDT, we’ll see how it works out for Vick and the Eagles.

“I could never imagine in the NFL situation, playing for an NFL team and getting the ball snapped that fast,” Vick said, “and getting plays signaled in and out consistently that fast to disrupt timing for the defense.”

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