The case for keeping Kevin Kolb has been made several times since the end of last season, and on its surface, the argument is reasonable.

With Michael Vick's style of play and an offensive line that has question marks, the Eagles could very well need a backup to step in at some point next season.

So the question is simple: Is Kolb's value as a backup greater than what the Eagles could potentially get in return for him?

If you've been paying attention over the past few months, you know my answer to that question is no.

But there is precedence here. Vick is not the only quarterback who has presented a health concern during the Andy Reid era. Didn't we go through a similar exercise to some degree during the Donovan McNabb era?

During his first two years as a full-time starter, McNabb played all 32 games. But in 2002, he suffered a broken ankle in Week 11 against the Cardinals (still, of course, managing to throw four touchdowns in the game).

The Eagles were 7-3 after winning that game, but the season was in question as McNabb would not return until the postseason.

Koy Detmer was called on to start the Week 12 game against the 49ers. He posted a 118.0 QB rating, and the Eagles improved to 8-3. But Detmer was injured in the game, and A.J. Feeley took over. With him behind center, the Eagles won four in a row before dropping the season finale to the Giants. They earned the No. 1 seed in the NFC before McNabb returned in the divisional round against the Falcons.

Overall, the Eagles were 5-1 without McNabb.

Did Detmer and Feeley play like superstars? No. Together, they had a QB rating of 79.9. And truth be told, the Eagles' defense was outstanding that season, limiting opponents to 15.1 points per game. But that team's offensive weapons didn't compare to the current Eagles' roster either. They had a running game, but James Thrash and Todd Pinkston were the team's leading receivers.

McNabb stayed on the field in 2003 and 2004, but suffered injuries in each of the next two seasons.

In 2005, the Eagles were 4-5 after a loss to the Cowboys in which McNabb suffered a season-ending injury. This time, the results without him weren't as impressive. Mike McMahon started the remaining seven games, and the Eagles won just two of them, finishing at 6-10, the second-worst record of the Reid era. McMahon and Detmer combined for a dismal QB rating of 49.42.

But just as the defense helped the Eagles in 2002, it was part of the problem in 2005, allowing 24.2 points per game (27th in the NFL). Terrell Owens was gone after seven games, and the Birds were not exactly stacked with offensive firepower.

A year later, McNabb went down in Week 11 against the Titans. In probably the biggest success story of these sorts, Jeff Garcia filled in. After a loss to the Colts dropped the Eagles to 5-6, they rebounded to win five in a row and take the NFC East title before losing to the Saints in the divisional round.

In the four games Garcia started (not including Week 17 against Atlanta when he threw just three passes), he put up a QB rating of 105.97.

Those are the three instances (pre-Kolb) that the Eagles had to count on a backup QB for three or more regular season games. In 2002, they relied on a good defense and QB play that was good enough. In 2005, the QB play was bad, but so was the rest of the team. And in 2006, the QB play was better than anyone could have expected.

What's the point here? The Eagles can probably find a backup quarterback that is good enough to fill in for Vick in the event that he goes down. Will the alternative be as good as Kolb? Probably not. In five games where he started as a backup, Kolb had a 91.6 QB rating, and the Eagles went 3-2.

Those are good numbers, but are they good enough to warrant holding on to Kolb and letting him potentially walk for nothing after the season?

I say no. Especially if the Eagles are able to acquire a defensive starter with a high ceiling in exchange for him.

And one more note on Vick. Rather than plan the offseason strategy around the idea that he's likely going to get hurt, doesn't it make more sense to try and figure out a way to limit the beating he takes?

It sure seems that way. Isn't that why they brought Howard Mudd in and drafted Danny Watkins? Isn't that why Marty Mornhinweg has talked about Vick still needing to improve his decision-making?

It's always difficult to try and predict injuries. While Vick certainly takes more of a beating than most NFL quarterbacks, consider this: In five seasons with the Falcons, from 2002-2006, he missed more than one regular-season game just once. That was in 2003 when Vick started four games. In the other four seasons, he started 15, 15, 15 and 16 games, respectively.

The obvious question to close with is: If the Eagles trade Kolb, who will they tab as their backup? has a list out of potential free agents: Matt Hasselbeck, Alex Smith, Marc Bulger, Bruce Gradkowski, Trent Edwards, Tyler Thigpen and others.

Are the names exciting? Not really. But Feeley had not started a game before 2002, and his performance was good enough to make the Dolphins give up a second-round pick for him before the '04 season.

Detmer never played a down for another team. And Garcia, the most talented of the group, had a couple bad seasons in Cleveland and Detroit before the Eagles added him. 2006 resurrected his career as he went on to have a couple more decent seasons with the Bucs.

Reid has been here for 12 seasons, and at this point, it's much easier to notice the negatives than the positives. But the truth is this has been one of his strengths, getting the team to rally after the quarterback or another key player goes down. He and Mornhinweg have a track record with quarterbacks, and history shows it's reasonable to expect they'll be able to find a backup to hold down the fort in the event that Vick goes down.

That's why Kolb's value as a backup is overstated and why dealing him once the lockout is the only move that makes sense.

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