(RELATED CHART: Breaking down Nick Foles)

THERE'S NO way to know for sure what the Eagles have in Nick Foles.

He's played 23 quarters and has started five games since replacing Mike Vick as the Eagles' quarterback. He's thrown 217 passes, some very good, some OK, some not so good.

You can look at him right now and pretty much see whatever you want to see. If you want to believe he can be the Eagles' starting quarterback for the next decade, you can see that in him. If you want to believe he's the second coming of Kevin Kolb, you can see that, too.

"If you're the Eagles, you're probably cautiously optimistic right now that this can be your guy," said NFL Network analyst Mike Mayock. "By cautiously optimistic, I don't mean you're sitting there saying, 'OK, we've got our guy here for the next 10 years.' It doesn't mean you're not looking to upgrade the position.

"If I'm them, I'd be grinding the heck out of these quarterbacks [in the draft] this offseason. If there's somebody I like in the first or second round that I think can come in and compete for the starting job, I'm drafting him. Because to put all of your eggs in one basket after a very limited evaluation period is a lot to ask, I think."

The Eagles did that 3 years ago and it didn't work out so well. They selected Kolb in the second round of the 2007 draft, let him sit behind Donovan McNabb for 3 seasons, watched him throw just 130 regular-season passes, then put McNabb on an Acela Express to D.C. and handed Kolb the starting job until death do us part.

His reign as "The One" lasted exactly two quarters before he got hit by Clay Matthews and suffered a concussion. He became "The Two" before trainer Rick Burkholder could ask him how many fingers he was holding up. A year later, Kolb was banished to the Arizona desert and hasn't been seen since. He is believed to be in witness protection.

Now, they need to figure out what they have in Foles, which probably is going to take longer than the two remaining games against the Redskins and the Giants.

"I think there are enough examples of guys out there, whether it's Matt Flynn or Kolb or A.J. Feeley, there are a lot of guys who have played pretty well for short periods of time," Mayock said. "But when the league gets a good look at you . . . take a look at the guy in Carolina [Cam Newton] right now. When the league gets 16 games on you, and they spend a full offseason planning for you, things get a lot more difficult. These guys that are game-planning you aren't dumb."

Foles has had his ups and downs since replacing Vick 6 weeks ago. Was shaky in his first start against the Redskins, completing just 21 of 46 passes, eight of 18 against the blitz.

Played much better the next three games against the Panthers, Cowboys and Bucs, completing 66 percent of his attempts and throwing three TDs and just one interception.

Was playing pretty well against the Bengals last Thursday until that much-discussed underthrown interception in the third quarter.

Mayock wasn't a big fan of Foles heading into the draft last April. Had a fifth-round grade on the kid, which was two rounds later than where the Eagles took him. "Coming out of the Senior Bowl, I kind of felt he had good but not great arm strength and kind of heavy feet," he said. "I didn't like his feet.

"Ironically, what I do like about him now is I think his feet are better than I thought they were. He's got a feel for sliding and moving in the pocket. I think he redefined his body. He looks like a completely different guy from what I saw at the Senior Bowl a year ago. And I think that's really good."

In his preparation for last week's game, Mayock went back and watched every throw Foles has made this year, including the ones in the preseason. Watched him practice for 2 days at Nova-Care, then watched his 16-for-33 performance against the Bengals.

"I liked what I saw when I watched him at practice," Mayock said. "At the quarterback position, I look for the intangibles as well as what you see on tape. From what everybody tells me, it looks like the kid is a gym rat. And he cares. And he's there early and stays late. Those things are really important.

"I don't know if he's got a big arm or not. But I know he can throw the intermediate route."

Foles has an 88.0 passer rating, including a .764 completion percentage, on attempts of 9 yards or less. Has an 82.6 rating on attempts of 10 yards or more, including a .471 completion percentage.

"That one throw [against the Bengals] doesn't bother me," Mayock said. "When you look at a snapshot of four or five games, there's some balls that I don't like that are intermediate to deep.

"It looks like every once in a while he throws a little bit of a flutter ball where he kind of loses control of it. The tightness in the spiral's not there. The velocity's not there. You could see it [on tape] once or twice a game. So, by itself, that one throw is no big deal. The question is, does it continue to happen?

"I came away from the Cincinnati game saying, 'OK, he made one really bad throw. But he made a bunch of good ones, including the one that Clay Harbor fumbled. He put that into a tight window. Overall, I thought he did some pretty good things against a defense that is playing at a high level."

Foles has been impressive in the pocket, both with his awareness of the rush and his ability to move around and buy time while keeping his eyes down the field.

"Like a lot of long-limbed quarterbacks that come into the league, he has to speed up the [throwing] process," Mayock said. "All of the guys like Joe Flacco and Josh Freeman and those 6-6 kind of guys that come into the league, even though most of them are pretty decent athletes, their process is so long because they're long guys. You've got to speed the whole thing up.

"In college, they don't work on that a lot. There's not a lot of sliding and moving in the pocket. You catch the ball in the shotgun. There's no footwork at all. It's catch, rock and throw. You're not doing much.

"In the NFL now, even when you're in the 'gun, you're doing more. You're reading progressions. I think what the Eagles have done with him is really positive. I think they've forced him - and it looks like they're all over him - about hastening his process in all aspects."

It obviously would make life a lot easier for the Eagles if Foles is "The One." It would be one less bell to answer, one less very big need to fill. But they aren't going to know for a while, no matter what happens the next two Sundays.

"I think you can easily talk yourself into [believing you have] a franchise quarterback," Mayock said. "But if I'm them, I wouldn't be jumping up and down, saying, 'I've got my guy.' I'd be saying, 'We may have a good young building block here. But we still have to figure that out.' "

On Twitter: @Pdomo

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