Chip Kelly's public admiration for Marcus Mariota doesn't necessarily mean the Eagles coach thinks the Oregon star is an NFL franchise quarterback, let alone one whom he would be willing to mortgage the future on by trading up in the draft.

But Kelly's effusive praise and the Eagles' continued uncertainty at the position make the prospect an intriguing one, even if the odds of it happening are slim.

What would it take to get Mariota?

A lot.

Would it be worth the price? It depends on whom you're talking to.

The Redskins, for instance, gave up three first-round picks and a second-rounder to move up four spots to No. 2 and select Robert Griffin III in 2012.

Mariota is the overwhelming favorite to win the Heisman Trophy on Saturday. Kelly said that he predicted the Oregon quarterback would one day win the award given to college football's most outstanding player when he was his coach and Mariota was a freshman.

"He's a special player, and he's just got a gift for playing football," Kelly said Thursday. "He's everything you want. He can throw the ball. He can run. He's the most talented kid I coached in college."

If Kelly was so clairvoyant about Mariota then, how accurate could he be about his NFL future? Asked to assess the 21-year-old in the two years since he left the program, Kelly said that he hasn't watched enough to give an informed opinion.

"Their games are on so late," Kelly said. "Sometimes I watch the first half and I fall asleep. I haven't gotten a chance to watch a full body of work from him. Anything he does numbers-wise . . . doesn't surprise me. But I think it's how he handles himself, his demeanor, and all those things that really kind of set him apart."

Some draft analysts have already projected Mariota as a top-five pick next year. Some have said he could go No. 1. It's a long way until April, though. Oregon, which qualified for the four-team college football playoff, has at least one more game to play. And Mariota has to go through the rigorous predraft process.

But it seems unlikely that a quarterback with his size (6-foot-4, 200 pounds), athleticism, and raw talent would drop out of the top five. If the Eagles are to have any chance of landing Mariota - their first-round pick is likely to be in the 20s - they would need a team already invested in a quarterback to own a top selection.

The 2-11 Jaguars drafted Blake Bortles third overall in May. They're the only one of the eight likely teams that could still finish with the league's worst record that wouldn't be interested in taking Mariota first overall. The 2-11 Raiders, who chose Derek Carr in the second round, could pass, as well.

The 4-8-1 Panthers with Cam Newton and the 4-9 New York Giants with Eli Manning may not yet be ready to draft a first-round quarterback, either. But the 2-11 New York Jets, the 2-11 Titans, the 2-11 Buccaneers, and the 3-10 Redskins likely will be in the market.

Even if the Jaguars or Raiders have the No. 1 pick and were willing to deal, or if Mariota fell a few spots, would Kelly be willing to give up so much? The Eagles have other holes to plug, and Kelly has managed to win two-thirds of his games without a "franchise quarterback."

Nick Foles could still be that guy, but he has regressed this season. He also has missed the last five games with a broken collarbone and might not get an opportunity to play again and prove he deserves a contract extension this offseason. His replacement, Mark Sanchez, hasn't done enough to suggest he could be more than a stopgap.

Asked what he knew now about the quarterback position in the NFL that he didn't before his arrival, Kelly said: "Nothing. I knew what it takes to win before I got here. You've got to have a really good quarterback who is a good decision maker that puts yourself in position to make plays and win."

Kelly noted that three of the top four college teams had strong quarterback play. And when a reporter pointed out that three of the four NFL teams with 10 wins had Aaron Rodgers, Tom Brady, and Peyton Manning as their quarterbacks, he joked: "We may be on to something."

Eagles receiver Josh Huff, who played with Mariota for three seasons at Oregon, said his former teammate could have that kind of ability.

"He might be the next Peyton Manning or Tom Brady - one of those guys," Huff said. "And he can move. Mix that in and he's like Michael Vick with a Manning-Brady mind."

Mariota this year has put up unbelievable numbers as both a passer (68.3 completion percentage, 3,783 yards, 38 touchdowns, and only two interceptions) and a runner (669 yards and 14 touchdowns). Some scouts have wondered, though, whether his success has been a product of Oregon's spread offense.

One scout was recently quoted anonymously as saying Mariota doesn't have the alpha-male quotient NFL quarterbacks often need.

"Some of my buddies are still within the program and they want him to actually be . . . meaner," said Eagles linebacker Casey Matthews, who left Oregon after Mariota's redshirt freshman year. "I heard that scout say he was 'too nice.' He seems to not do anything wrong, although he got a speeding ticket two weeks ago."

Said Huff: "He definitely has some fire in him. He just doesn't show it."

Kelly is likely to disagree with those who think Mariota is "too nice" to thrive in the NFL.

"I had nothing to do with Marcus," he said. "When he was a freshman, I remarked: 'This kid is going to win the Heisman.' He's a special young man, and he's a hell of a football player, and he deserves it."

Cox the fox

Fletcher Cox's ascension into the upper echelon of defensive linemen in his third season has not been just a by-product of his athletic abilities.

The defensive end has proven to be a quick study in deciphering offensive moves. For instance, against the Seahawks on Sunday, Cox stood up and motioned to the rest of the Eagles' front seven where a run play was going, according to linebacker Mychal Kendricks.

"For a defensive lineman to stand up out of his stance and point and say, 'The ball's going this way, the ball's going that way,' is crazy," Kendricks said. "It's never happened to me. And for him to do that, it lets me know he's stepping up into a certain role as well."

Later in the game, Cox lined up just over the center's outside shoulder. He typically has two-gap run responsibilities (lining up directly over an offensive lineman) in the base defense, but Cox said he read which way Seattle intended to block and improvised.

He shot through the gap past the guard and recorded a tackle for loss. It was one of 12 solo tackles Eagles coaches gave him credit for.

"Of course, they want us two-gapping," Cox said, "but they want us to be football players, too."

Cox had some initial struggles last season in the new 3-4 scheme, but he said defensive line coach Jerry Azzinaro has given him more leeway this season because of his consistent play. Defensive coordinator Bill Davis said, "It was tough to block him this past weekend."

Cox agreed.

"That's how I feel, and that's what I tell myself," Cox said. "If I'm doing my job 100 percent every time, it's scary."

Inside the Game

It was as if Chip Kelly came prepared with numbers knowing full well he was going to be asked about the disparity in deep-passing success between this season and last.

"Last year we saw 60 percent man, 40 percent zone," Kelly said Wednesday. "Right now we see 58 percent zone, 42 percent man."

Kelly's point, and the narrative from Eagles such as receiver Riley Cooper this week, is that the drop in deep passes is because defenses are playing deeper in zones.

"Teams are playing us a little bit different this year. The majority is zone," Cooper said. "So it's tough to get past that for the deep balls. . . . Those deep balls teams are taking away. So we got to come at them a little differently - dink and dunk and get the run game going."

Whether defenses were eliminating the deep balls when Nick Foles was at quarterback or not, he took more chances attempting passes over 20 yards in eight games this season (59) than he did in 11 games last season (55).

Foles was more accurate in 2013, however, completing 25 passes for 803 yards and 14 touchdowns with one interception vs. 19 completions for 578 yards and nine touchdowns with six interceptions before his injury.

Mark Sanchez hasn't had as much success with the deep ball. He has completed 9 of 26 attempts for 281 yards and one touchdown with two interceptions.

"Last year we set an NFL record for explosive plays," Kelly said. "So I didn't think anybody thought they would play us the same way. So usually if the ball is getting thrown over your head, I think people are going to back up more."

DeSean Jackson caught 17 deep passes for 593 yards and eight touchdowns, and Cooper caught seven for 280 yards and five touchdowns last season. While Jeremy Maclin has picked up some of Jackson's slack (eight catches for 334 yards and five touchdowns), Cooper's deep numbers are down (three for 92 yards and no touchdowns).

"I just think we had so much success last year getting singled - DeSean and myself," Cooper said.

Inside the locker room

The Eagles practiced in snowy conditions Thursday, but there was a reward at the end. Players were greeted by a bowl of hot chocolate and marshmallow fixings as they entered the locker room. The mix had a special ingredient, but the recipe was not for public consumption, the Eagles said, taking the team's sports-science program to even greater secretive heights.

Five Questions: Darren Sproles

Q: If you were NFL commissioner, what would be the one thing you would change about the league?

A: We wouldn't get fined for not talking to the media.

Q: What is your most treasured possession?

A: My family.

Q: Where would you like to live most?

A: San Diego.

Q: Who wins a fight between a bear and a shark in five feet of water, and why?

A: I would say the shark, because once his jaws lock it's over with. He's going to tear him apart.

Q: If you could be any fictional character, who would you choose?

A: Superman.

By the Numbers

15.4: Ratio of targets per interception to wide receiver Riley Cooper. Of the 89 wide receivers with more than 40 targets, only four (Kenny Britt, Andre Roberts, Cordarrelle Patterson, Torrey Smith) have a worse ratio.

101: Defensive pass-interference penalty yards charged to cornerback Bradley Fletcher, who has been flagged four times this season. Only two players (Darius Slay, Blidi Wreh-Wilson) have surrendered more pass-interference yards.

12.3: Jeremy Maclin's per-catch average (33 catches for 407 yards) with Mark Sanchez at quarterback. The receiver's average with Nick Foles was 17.1 (41-702).

@Jeff_McLane