IT WILL fade into Eagles history as little more than a speed bump either on their road to relevance or, if they continue to struggle, on their continued path toward futility.

It should not be allowed to fade.

The Eagles on Tuesday traded one of the main building blocks for their reconstitution, veteran nose tackle Isaac Sopoaga, a seven-game starter, for, essentially, nothing.

The more obvious drafting mistakes - guard Danny Watkins and safeties Jaiquawn Jarrett and Nate Allen - overshadowed the more egregious errors in shopping for pro personnel, such as the $3.25 million mistake Sopoaga has been.

It is the earmark of teams that fail to compete: a Demetress Bell here, a Jarrad Page there, a Vince Young or Ronnie Brown thrown in for seasoning.

A 3-4 team doesn't trade its only true nose guard and a sixth-round pick for a fifth-round pick unless that player simply cannot play. The Patriots assumed the remaining $1.5 million or so still due Sopoaga.

"I thought Isaac did a nice job for us," Eagles coach Chip Kelly said.

Well, Sopoaga, 32, collected 10 tackles, a pace to tie his career low. He has had one sack in his last 38 regular-season games.

If that's a nice job, what would be a poor job?

Wiki-leaking the game plan?

"The effectiveness of a nose tackle in the NFL is not always going to show up on the stats page," said Eagles general manager Howie Roseman.

Fair enough. However, the most meaningful stat always is games played. Effective nose tackles in the NFL don't get traded with eight games left to play.

The Eagles passed on Sopoaga's former 49ers teammate, 26-year-old Ricky Jean Francoise, who visited with the Eagles but landed with the Colts for twice as much guaranteed money. That, Roseman said, was too much money to commit to Francoise, a player loaded with potential but with modest production in his first four seasons (and, really, with modest production so far in his fifth season).

The Eagles were looking for a knowledgeable player adept at nurturing their crew of younger players learning a new system without being threatened by them. Fletcher Cox and Cedric Thornton started alongside Sopoaga. They benefited most.

"We were transitioning from a 4-3 wide-nine to a 3-4 two-gap," Roseman said. "Sopoaga helped them through that transition because of his experience in the scheme and his experience in the league."

Sopoaga's experience helped educate rookies Bennie Logan and Damion Square, as well as Clifton Geathers, who ran a different sort of 3-4 with the Colts before he was traded.

All of those players would have benefited more had they seen Sopoaga better practice what he preached. The reality is, Sopoaga is the latest in a line of recent poor personnel moves involving second-tier veteran players.

The worst was last year's acquisition of Bell, who was signed to replace injured left tackle Jason Peters. Bell made $3.2 million in 2012. Bell started just five games. The Eagles cut him in February to avoid paying him any more of the 5-year, $34.5 million contract to which they had signed him.

If Bell wasn't the most damaging signing, it was that of safety Page, a Patriots castoff who followed a path almost identical to Sopoaga's.

Page was signed as a backup but he shined in training camp in 2011. So, he started the first five games of the 2011 season, and helped lose four straight after an opening-week win. He was the worst player on the team (with all due respect to guard Kyle DeVan). Page blew coverages. He missed tackles. He couldn't run and he couldn't hit. His very presence essentially sabotaged the scheme of unlikely coordinator Juan Castillo.

Because he made minimal money, Page wasn't as big a mistake as top-tier veterans such as Nnamdi Asomugha and Dominique Rodgers-Cromartie. But he was expected to play.

Page was cut after playing six games.

Sopoaga made it only eight.

A pleasant fellow, Sopoaga landed in Philadelphia with a reputation for effectively executing the sorts of trench maneuvers that lead to tackles for ends and linebackers.

Instead, Sopoaga mainly got washed out of plays, often by only one blocker. In his ninth season, he stands 6-2 and is listed at 330 pounds, but, frankly, that weight seems bogusly high.

By the end of the season, Sopoaga might not even be the worst mistake the Birds made in this category.

Free-agent safety Patrick Chung has done little to warrant his $4 million in guaranteed money. In fact, the position saw a significant upgrade when fourth-round rookie Earl Wolff took over the past two games, as Chung watched with an aggravated shoulder injury.

Chung's toughness and professionalism cannot be questioned. His ability can.

It's as if the Eagles cannot learn: Seldom does Bill Belichick allow a value-laden veteran to escape New England.

He let Page walk. He let Chung walk, too.

Chung, who started the first three games and the sixth game as well, will cost the Eagles $3 million this season and is guaranteed $1 million more of his 3-year, $10 million contract; unless, of course, someone trades for him. Maybe he has been a godsend as a voice in speeding the development of Wolff and Allen.

As it turns out, the Eagles had three young players in Geathers, Logan and Square whom they like more than Sopoaga. They didn't know how good those players would be, or how unremarkable Sopoaga would be outside of the classroom.

Roseman pointed out that no team hits on every veteran acquisition; that every team whiffs on players who have either reached their expiration date or who effectively camouflage deficiencies.

All that said, trading away a $3.25 million, part-time coach in the middle of the season for essentially nothing is the admission of a significant mistake.

"When you look at it from a financial perspective, it's not what you're looking for," Roseman said. "You don't have the luxury of that information when you're making those decisions."


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