Chip Kelly first watched Washington Redskins quarterback Robert Griffin III when he was a prospect on Oregon's radar during the spring of 2007. Griffin was also a world-class track athlete at the time, the beginning of his emergence as a promising dual-threat quarterback.

That promise has been unfulfilled during the last two seasons, ever since Griffin collapsed to the ground in a January 2013 playoff game with a knee injury. Griffin rushed to return for the 2013 season opener - which happened to be Kelly's debut as Eagles coach - and he was neither the same passer nor rusher during a forgettable second season in Washington.

His career continued its decline this season, with injuries affecting him before coach Jay Gruden demoted him last month. But Griffin is back for another stint as starter, starting with a home game Saturday against the Eagles. It's a chance for Griffin to begin restoring his reputation. But Kelly seemed bewildered by the idea that Griffin might not be the same athlete he was before the injuries.

"If you sleep on that guy, trust me, [reporters] will be sitting here after the game going, 'Boy, he went for a hundred yards against you, how did that happen?' " Kelly said. "That kid is athletic as heck, and he can run really, really well. Trust me: We have to understand where he is on every single play."

The Eagles expect to see a different Redskins offense than the one they saw when Washington quarterback Kirk Cousins threw for 427 yards in the Birds' Week 3 win.

Griffin was injured at that point, and Washington has not won any games that he started and finished this season. This comes after Griffin was 3-10 last season. However, Eagles defensive coordinator Bill Davis said Griffin is "still a dynamic player," and he made those comments after watching Griffin pass for 236 yards and rush for 46 against the Giants on Sunday.

"He really looked like he benefited from a little bit of perspective in taking a step back and looking at it," Davis said. "He came out there with a little more confidence and that old swagger you saw. He ran the ball more aggressively, he put the ball on the money, he threw the ball a little more accurately, and it looked like he had a better understanding."

Gruden, who has seemed to use tough love in his comments to get through to Griffin, told Philadelphia-area reporters on a conference call this week that Griffin must improve on his decision making and getting the ball out of his hands. He noted that Washington has taken too many sacks and must speed up the process.

When Griffin led Washington to the NFC East title as a rookie in 2012, he threw for 3,200 yards with 20 touchdowns and five interceptions while rushing for 815 yards and seven touchdowns. Gruden said Griffin's injuries are one reason the quarterback has not been the same, citing Griffin's rushing stats from 2012.

"That element of the zone read was a little more of a threat than it is now, most likely," Gruden said. "Defenses now [have] had a couple years to really game-plan against it, and it's a little more difficult to run a zone read from a consistent basis. You want to sprinkle it into your offense here and there, but you can't make a living running it right now because quarterbacks get injured."

Gruden added that Griffin is seeing more coverages and playing from the pocket more because Washington is facing many third-down situations. Pro-style quarterback play is "something he's not used to doing," Gruden said.

The Eagles' best way to beat Washington would seem to be making Griffin a pocket passer. Most of the team's discussion about him this week has focused on his rushing.

The Eagles have faced five of the NFL's most mobile starting quarterbacks this season. They contained Cam Newton and Andrew Luck on the ground, although the defense was vulnerable when Russell Wilson, Colin Kaepernick, and Aaron Rodgers used their feet. Wilson rushed for a 26-yard touchdown, and Kelly said this is the Eagles' biggest challenge from a rushing quarterback other than Wilson.

"You saw what happened to us," Kelly said. "I thought we did a really good job at times in defending Seattle, and then all of a sudden Russell just extended plays and continued to make things happen."

Linebacker Connor Barwin said the Eagles must be disciplined with their pass rush, with their eyes always on the quarterback. They cannot slow down the rush, but they cannot take as many calculated risks. Barwin and linebacker Mychal Kendricks will likely be the two linebackers tasked with trying to keep Griffin from exploding for a big gain.

"I'm expecting him to be fast," Barwin said. "And I'm preparing like he's going to be able to run like he used to be able to run."