Building a roster under the constraints of a hard NFL salary cap involves finding value. Howie Roseman managed to do this effectively in the past. It was his superpower, it seemed.

There would have been no Super Bowl LII win without defensive linemen Chris Long, an aging free agent, and Timmy Jernigan, a low-cost trade piece. No title without running backs LeGarrette Blount, a 31-year-old bargain, and deadline acquisition Jay Ajayi, who had just enough knee cartilage left to carry the Birds in the second half of the season.

Roseman re-signed offensive lineman Stefen Wisniewski after the 2016 season, and Wiz started all three playoff games. Patrick Robinson was one of the best slot cornerbacks in the league in 2017, and, at 30, he cost just $775,000 — money he earned with his pick-six in the NFC championship game alone.

After two seasons of specious signings, the Eagles needed their bargain-hunting general manager to be his best in 2021. Lots of problems loomed.

They had a rookie head coach and an inexperienced coaching staff. Almost all of their best players — Fletcher Cox, Brandon Graham, Brandon Brooks, Jason Kelce, Zach Ertz, Lane Johnson — were 30-something.

Howie lost his mojo, it seems.

That’s a big reason the Eagles are 1-3. If they hope to avoid going 1-4, they will need a lot more from the players Roseman added or extended as depth pieces.

Big name, no game

Roseman’s biggest stopgap signing was Ryan Kerrigan, who left Washington as its all-time sack leader, with 95½. Nobody expected Kerrigan, at 33, to be the same Kerrigan who collected 13 sacks and went to his fourth Pro Bowl in 2018, but Kerrigan managed 11 sacks over his last two seasons with Washington.

Through four games not only is Kerrigan sack-less, he also doesn’t have a single tackle. Not one assist.

In 116 defensive snaps he has just five quarterback pressures — which means, effectively, he’s getting within arm’s reach of the quarterback about once per game. He’s making $2.5 million. He’s not earning it.

Kerrigan was supposed to relieve Brandon Graham, a bookend backup with Josh Sweat, who collected 10 sacks as a backup the last two seasons.

Last month, Roseman gave Sweat a $40 million extension with almost $27 million guaranteed. In return, Sweat has given Roseman a half-sack and four quarterback pressures.

These near-zeros at the defensive end position are amplified by the absence of Graham, who was lost in Game 2 to a ruptured Achilles tendon. Graham’s absence was supposed to amplify their presence. He’s 33. They were his insurance policies.

The policies have not paid off.

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Dead last

At least Kerrigan and Sweat were supposed to be insurance policies. The Eagles signed linebacker Eric Wilson for up to $3.25 million in hopes that the Vikings’ leader in tackles, with 122, would provide a measure of proficiency.

Yes. Well.

Wilson ranks dead last in overall play and run defense among linebackers with at least 52 snaps, according to profootballfocus.com. Their grading seems generous.

Wilson isn’t alone at the bottom. That’s where J.J. Arcega-Whiteside resides, too. Roseman couldn’t bear to cut the third-year receiver, who has been a bust since the day he drafted him in the second round in 2019, despite the fact that JJAW caught just 14 passes in his first two seasons.

Those were the days.

He’s at zero this season.

You guys there?

Roseman snagged former Steelers corner Steven Nelson for $4 million to flesh out his starting three, but Nelson hasn’t done much except keep receivers in front of him and harry them out of bounds.

Roseman spent $5 million on safety Anthony Harris because Howie couldn’t count on second-year fourth-rounder K’Von Wallace or third-year man Marcus Epps, but both Wallace and Epps have outplayed Harris.

It’s not as if other Eagles have shined as they should. Cox is slowing down at defensive tackle, defensive end Derek Barnett keeps stealing money with poor production and penalties, and tight end Ertz has 13 catches in four games.

Roseman was pot-committed to players like them.

He sought, extended, or retained several veterans who were supposed to make a difference.

Sunday in Charlotte would be a good time for them to start.

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