Mullens now faces a coaching search amid recruiting season.
"I've turned the page," Mullens said. "I was surprised when I got the call this morning, but as the leader of this organization, my focus is on moving forward and that's what we're doing. I'm laser focused on what's next, and that's finding the right fit to lead Oregon football."
It's unknown whether the possibility of NCAA sanctions based on Oregon's use of recruiting services factored into Kelly's reversal. He indicated in Arizona that he isn't running from anything.
"We've cooperated fully with them," he said. "If they want to talk to us again, we'll continue to cooperate fully. I feel confident in the situation."
Kelly doesn't have any pro coaching experience, but aspects of his up-tempo offense are already being used by New England and Washington.
The Eagles fired Reid after two forgettable years. A late flurry brought the team to an 8-8 finish last season, but this season, Philadelphia endured an eight-game losing streak, and dropped 11 of its final 12. A 3-1 start soon washed away, and Reid's 14-year tenure ended not long after. Within a week, Reid was Kansas City's new coach.
Still, Kelly has tough shoes to fill. Reid won more games than any coach in franchise history and led the Eagles to nine playoff appearances, six division titles, five conference championship games and one Super Bowl berth.
Kelly and the Eagles have the No. 4 overall pick in the draft as well as some talented players on offense who could fit his scheme. Running back LeSean McCoy and receivers DeSean Jackson and Jeremy Maclin seem like ideal matches. Quarterback Nick Foles, however, isn't.
"I've never run the zone read," Foles said after the season. "I'm more of a dropback guy. I've been under center. I've been in the gun. If I can adapt, I want to. But I'm not a zone-read quarterback. Some people are gifted with different things. That's just not one of my skill sets. I can work on the speed in the offseason and get better with that. But I've always been a dropback guy in the pocket. I've been able to make plays on my feet throwing the ball or running for a first down."
On the other hand, Michael Vick could be perfect. But it's unlikely the Eagles would want to pay the $16 million they'd have to shell out for an injury-prone quarterback, who will be 33 next season.
Kelly had high praise for Foles after Oregon beat Arizona 56-31 in September 2011.
"I'll tell you what; I'm glad Nick Foles is graduating," Kelly said at that time. "I catch myself watching him in awe sometimes. Nick is a hell of a football player. That kid's a warrior. He's as good as anyone in the country."
Others interviewed by Philadelphia were former Bears coach Lovie Smith, Atlanta assistants Mike Nolan and Keith Armstrong, former Broncos offensive coordinator Mike McCoy and Bengals offensive coordinator Jay Gruden.
The first Eagles to react to Kelly's hiring on Twitter were defensive players.
Defensive end Brandon Graham wrote: "Happy to have Chip Kelly!! Now it's time to get to work!"
Safety Kurt Coleman wrote: "Welcome Chip Kelly to the Eagles family. Can't wait to see what he brings to the team in 2013!"
As he walked by the fans at the airport, Kelly, dressed in jeans and a sweat shirt, stopped to sign some autographs and share some laughs with the faithful.
It indeed was a long journey. But if Wednesday is any indication, Kelly appears to fit right in with Philadelphia.
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