"I think you have a body of work so you understand what the opponent is about," Kelly said.
The second Giants game was different from the first, the coach said, and again this Sunday both teams can be expected to make adjustments: "We've got some experienced guys on our staff that have been through it before, and that's always the deal."
Kelly's point is accurate: The Eagles lost to the Giants not because New York had previous exposure to the Birds. The Giants had key players in that second game who were absent in the first game. That will also be the case this weekend. Kelly pointed to Washington safety Brandon Meriweather and linebacker Rob Jackson, who missed the teams' first meeting.
The Eagles are also a different team this week. The biggest change will be at quarterback, where Nick Foles will start instead of Michael Vick. Vick excelled against Washington, and it's a different dynamic with Foles behind center. As much as a dangerous running threat helps, Washington coach Mike Shanahan said this week that players who throw for 16 touchdowns and zero interceptions "don't fall out of trees."
Foles' preparation has included watching the film from the opening game as well as from Washington's most recent games. He said it's helpful to see how Washington defended the Eagles, but the recent games have given him a better indication of the defense he will see Sunday.
Kelly continues to insist that the Eagles run the same offense with Vick and Foles. Washington linebacker London Fletcher observed that many of the concepts remain the same, although the Eagles have more of a deep-passing game than when the teams played in September. Beyond the personnel, Fletcher said it was helpful that the defense has been exposed to the Eagles' tempo.
"The fact that we've played it and faced it at least once I think will definitely be a benefit for us, as opposed to when we faced it at the start of the season," Fletcher said. "It's to our benefit to say we've at least faced it once. We got stuff on film now. Ten games of the Eagles to look at now, as opposed to none the first time around."
The Eagles defense did not know how quarterback Robert Griffin III would play in the opener, which was his first game back from a major knee injury. Griffin's mobility appeared limited in that game, but Griffin has been better in recent weeks. Shanahan said there's been "steady progress" since Week 1, and Griffin is more comfortable with himself and with the injury. That's one way Kelly said Washington is different from the first time the teams met.
"I think their offense has expanded. Our defense has expanded," Eagles defensive coordinator Bill Davis said. "I think they've grown their package, and he looks a lot more mobile than he was in the first game."
How both teams adjust could be the key to Sunday's game. But it's a part of the NFL that's new to Kelly. He never coached in a conference championship game in college, and postseason appearances never included rematches.
"You've got a body of work and you have a little bit of an understanding," Kelly said, "but it's not exactly the same as the first time."
Tackle Jason Peters (quadriceps and pectoral), linebackers Mychal Kendricks (knee) and Jake Knott (hamstring), and safety Earl Wolff (knee) all missed Thursday's practice. Wolff was already expected to miss the game, but the other three do not appear to be in line to play. Michael Vick (hamstring), tight end Brent Celek (hip), and cornerback Bradley Fletcher (pectoral) were all limited. . . . The Eagles signed wide receiver B.J. Cunningham to the practice squad and released cornerback Marcus Burley.