"To be completely honest with you," Umenyiora said, "if Philadelphia really understood his value to that team, they would never even have allowed him to get upset with his contract. You take Westbrook off that team and nobody would fear them. I don't think they truly understand that.

"You've got to game-plan against him. You've got to know where he is every play. As a defensive end, the things that we do change when he's in the football game. When you've got a player on your team like that, you have to take care of him.

"He should be one of the highest-paid players in the league. Period. I'm not saying this as a friend of his. I don't even know the guy that well. I'm just saying it because it's the truth."

Umenyiora might find this surprising, but the Eagles wholeheartedly agree with his assessment of the running back's value to their offense. Over the last two seasons, the guy has notched 4,020 rushing and receiving yards, which is 34 percent of the team's net yards over that period. A player everybody thought was too small to be an every-down back in the NFL had a league-high 687 touches in 2006 and '07.

They also agree that Westbrook has outperformed his current contract. He is entering the third year of a 5-year, $25 million deal he signed in November 2005, which is small potatoes for a guy who is no worse than the second-best running back in the league right now.

The dilemma for the Eagles isn't gauging Westbrook's worth to the team today. It's predicting what it will be tomorrow; what it will be 2, 3 and 4 years from now as he gets older and the physical pounding from 300-plus touch seasons begin to take a toll.

It might seem like Westbrook hasn't been around all that long, but he is entering his seventh pro season. He will turn 29 in early September, which is young for a doctor or lawyer or stockbroker, but close to retirement age for an NFL running back.

No position in football has a more dramatic production drop-off than running back. One minute you're bursting through holes for 8-yard gains, the next minute those holes are closing around you. Case in point: Shaun Alexander. Three years ago, the former Seahawks running back rushed for 1,880 yards and 27 touchdowns and was the league MVP. Now, just a couple of weeks shy of his 31st birthday, he can't find work.

Precious few NFL running backs have managed to remain really productive into their 30s. Former Rams running back Marshall Faulk, a versatile runner and receiver who was used much like the Eagles use Westbrook, had seven 1,000-yard rushing seasons before he turned 30, but none in the four seasons he played after hitting 29. His average-per-touch was almost a yard-and-a-half less in his final four seasons (4.43) than it was before he turned 30 (5.47).

Another all-purpose back, Thurman Thomas, who went into the Hall of Fame last year, had just one 1,000-yard rushing season in the 5 years he played after he turned 30. Eric Dickerson averaged just 3.72 yards per carry in his four post-30 seasons after averaging 4.58 in the 8 years before that.

Another Canton inductee, former Cowboy Emmitt Smith, had three post-30 1,000-yard rushing seasons, the last one at 32. But he averaged just 3.87 yards per carry after he turned 30 and 4.31 in the 10 seasons before that.

Former Jet Curtis Martin is a classic example of how quickly a running back can lose it. He had the best season of his career in '04 at the age of 31 when he rushed for 1,697 yards and caught 41 passes. A year later, he averaged just 3.3 yards per carry and was forced to retire because of bad knees.

There have been exceptions. Walter Payton continued to be productive into his 30s. Rushed for 1,000 yards three times after he turned 30. Had the second-best rushing season of his career at 30, when he had 1,684 yards. Notched his last 1,000-yard season at age 32.

Former Eagle Ricky Watters rushed for 1,000 yards in two of his three post-30 seasons. Had 1,855 yards from scrimmage in his next-to-last season, at 31.

Tiki Barber, to whom Eagles coach Andy Reid often has compared Westbrook, still was going strong when he retired after the '06 season at 31. Had 4,517 rushing and receiving yards his final two seasons.

"Tiki could've played a couple more years at a high level, I think," Giants general manager Jerry Reese said. "It's a young man's game, though. I do know that."

Another Hall of Famer, Marcus Allen, played until he was 37. Averaged 4.0 yards per carry and 8.8 yards per catch in eight post-30 seasons. Spent his last five NFL seasons with the Chiefs as a third-down and goal-line back, scoring 44 touchdowns in those five seasons. Never had more than 240 touches in any of those five seasons, which definitely helped extend his career.

"When I signed Marcus [in 1990], he was 33," Chiefs president Carl Peterson said. "I was hoping to get 3 years out of him. We ended up getting 5. He kept himself in excellent shape. In his entire 15-year career, he had just one minor arthroscopy to his knee.

"He knew when to get down and avoid the big hit. He had terrific peripheral vision. [Former Raiders coach] Art Shell used to call him horse-eyes. He could anticipate the hit coming."

Westbrook doesn't have Allen's clean medical record. He sat out a season at Villanova because of a knee injury. Has played the last two seasons with knee inflammation that has required occasional draining.

But what he does have in common with Allen is a knack for avoiding the big hit.

"Guys come at him from all angles, but he's very good at avoiding the harsh hits," Andy Talley, his college coach at Villanova, told the Daily News last November. "That's because he's smart about the way he runs and because he has great vision. Also, because he's short in stature [he's 5-8], he has great body lean and body awareness. It's really hard [for a tackler] to get under him."

John Harbaugh, the Baltimore Ravens' head coach and former Eagles assistant, agrees with Talley.

"Brian doesn't take a lot of big hits," he said. "I don't know who you could compare him to in that respect. Maybe Walter Payton. He never took a lot of big hits, either.

"Brian does it almost by going sideways past tacklers. He is, without question, the best athlete I've ever coached. It's so hard to describe his athleticism. But when you see it, you know it. Wow. Maybe that's the word. Wow."

One of the reasons the Eagles acquired running back Lorenzo Booker in April was to lighten Westbrook's load a little and try to extend his career. No matter how adept he is at avoiding big hits, no matter how many practices they sit him to rest his knee, he won't be long for the NFL if he continues to touch the ball 340-plus times a season like he has the last 2 years. Which brings us back to the issue of how much the Eagles should pay him.

"You always wonder when a guy is going to hit the wall," the Giants' Reese said. "With older players, you're always rolling the dice. You always want to try to reward the guys that have been good players, good soldiers for you.

"But you can't manage with emotions. You've got to make the right decisions for your football team. It's a delicate balancing act to make that work out. Sometimes you give 'em the big contract in the latter part of their career and sometimes you have to hold your ground and go in a different direction.

"Sometimes guys slowly decline and sometimes it's just a free fall. You look at the stats [to help you], but the stats will lie to you sometimes."

Westbrook's stats say he has been the NFL's most productive running back the last two seasons. But they don't tell you about next year, and the year after that, and the year after that. And that is the problem.

"There are guys that have done it [been productive after they've turned 30]," Westbrook said last week when he reported to training camp. "Can they continue to do it? That's the question. I'm hoping I can."

So are the Eagles. Only problem is, it's tough to put a dollar figure on hope. *