There is no replacing Brandon Graham. It’s that simple.

There may be another defensive end who matches or even exceeds his abilities in the NFL. And there may be another player who is as much of a leader. But it’s unlikely there’s anyone who possesses both traits, and there certainly isn’t anyone on the Eagles.

That being said, the Eagles do have candidates to fill either role, and not necessarily just one or two guys. It’s going to take a group effort. Coordinator Jonathan Gannon said he spoke to his defense Tuesday about the challenge of replacing Graham, who suffered a season-ending Achilles tendon rupture last Sunday.

“From a leadership, character, and attitude standpoint, everyone has to try and fill that void collectively, because not one guy is going to be able to do that.” Gannon said Wednesday. “We do feel good about the leaders that we still have within the defense.”

On the field, offsetting the loss will be split among several defensive linemen. Ryan Kerrigan, whom coach Nick Sirianni name-checked Monday, was Graham’s primary backup in the first two games. But it’s likely that Josh Sweat and Derek Barnett will both be moved to the left side on occasion.

Tarron Jackson was Kerrigan’s backup after Graham left, but the rookie struggled in 11 snaps. Gannon could certainly get away with a three-man rotation with his 4-3 front, but he has also employed a 3-4 with Sweat and Barnett in outside linebacker roles.

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Milton Williams has lined up almost exclusively inside, but the third-round rookie did cross-train in training camp. He can play end and would be a better option than Jackson, although that would make the Eagles lighter at defensive tackle.

Gannon has options, though, and more than most defenses. Graham’s absence does potentially hinder his plans to be multiple up front, but not if Sweat, Barnett, and company deliver on the Eagles’ investment in their D-line.

Who’s going to step up?

Josh Sweat

Considering the contract extension general manager Howie Roseman just gave Sweat — three years, $40 million with $26.92 guaranteed — he would seem to be the likely benefactor from Graham’s injury.

The 24-year old had steadily progressed in his first three seasons, and his performance in camp suggested that 2021 could be a breakout year. He didn’t disappoint in the season opener at the Falcons, even if he didn’t record a sack.

Sweat [No. 94] fought through two tight ends to force quarterback Matt Ryan to throw early and incomplete. He had two pressures in 22 rushes, but his run defense stood out most in Atlanta.

He can not only set the edge and force running backs inside, but also he can fight off blocks and make stops near the line.

And give him space and he can run down backs and use his 6-foot-5 length to bring them down.

Barnett has started both games, but Sweat has had a knack for making his presence felt early in games. On this rush against the 49ers on Sunday, he turned the edge and hurried quarterback Jimmy Garoppolo into an errant pass.

Sweat wasn’t drafted until the fourth round for several reasons. He suffered a devastating knee injury as a high school senior that derailed his career, and he played mostly out of position as a five-technique defensive end at Florida State.

He ended both the 2018 and 2020 seasons on injured reserve — with ankle and wrist injuries — but there will always be concerns about his left knee, which was completely dislocated.

Sweat played only 40% of the snaps Sunday, but with the 49ers offense using a lot of two-back and two-tight-end packages, his playing time was limited.

“Looking back on it, he should have played more there, too,” Sirianni said, “but that was just a design of what packages we were playing against the 49ers.”

The Cowboys, Monday’s opponent, are likely to employ a large number of three-wide-receiver sets and throw on early downs. Sweat should get more opportunities to rush the passer.

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Derek Barnett

The majority of Sweat’s rushes — 81.3% — have come from the right as opposed to the left tackles. Barnett has a similar percentage (81.6). Gannon was asked if switching sides affects edge rushers as much as it can for tackles on the other side of the ball.

“That’s a little case by case,” Gannon said. “How our guys are trained … since we’ve been here with [defensive line coaches Tracy] Rocker and [Jeremiah] Washburn, they feel pretty good playing multiple spots and both sides.”

One of Barnett’s [No. 96] three pressures this season came from the left side in Week 1.

Barnett, a former first-round draft pick, is a relentless defender. He hasn’t been a bust, but his production hasn’t matched expectations, partly because of multiple injuries. He isn’t especially large, and if he can’t turn the corner, he struggles with power moves against better left tackles like the 49ers’ Trent Williams [No. 71].

Penalties, especially personal fouls, have been a problem. Barnett picked up the eighth of his career Sunday when he hit a player after the whistle. It gave the 49ers a first down rather than a long third down.

“I can’t speak to anything that is in the past,” Sirianni said. “Obviously any personal foul is an unacceptable foul that happens after the ball is out of bounds, so that will be addressed.”

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Ryan Kerrigan

The Eagles signed the 33-year-old to a one-year, $2.5 million contract in the offseason. Kerrigan was brought in to be a situational pass rusher in the mold of Chris Long, who had two productive seasons with the Eagles as a fastball off the bench. But stylistically they’re different.

Long was ideally suited to Jim Schwartz’s wide-nine 4-3. Kerrigan spent most of his first 10 seasons in the NFL as a 3-4 outside linebacker. He did less dropping into coverage in later seasons in Washington, but rarely moved inside.

With the Eagles, he has played 4-3 end on most passing downs, and 3-4 end on most run downs. Kerrigan [No. 90] has as many pressures (3) as Sweat and Barnett, but he hasn’t yet done much rushing or defending the run as a down lineman.

Tarron Jackson

The sixth-round rookie played six snaps long after the outcome of the Falcons game was settled, but he played meaningful downs last Sunday. Trent Williams is a likely future Hall of Famer, but Jackson [No. 75] was clearly overmatched.

He needs time to build strength and work on technique. On the first rush, for example, he took too many steps in his approach. The 6-foot-2, 254-pound Jackson struggled even more when moved inside as a 3-4 end.

Milton Williams

Milton Williams could slide outside ahead of Jackson if need be.

“He will be a piece that we continue to use and move him around within the package and the call,” Gannon said. “We’re going to try and put him the best spot we can. … His play time will continue to be where it’s at and possibly even go up a little bit.”

Williams has had a relatively quiet start, but he clearly has potential. With Javon Hargrave arguably the Eagles’ best lineman so far, and Fletcher Cox still a force, they don’t have to rush the rookie. Hassan Ridgeway has also gotten off to a solid start.

It’s been tough sledding inside for Williams [No. 93], although on this play he might have been held. Perhaps more repetitions on the edge can free him up.

The opportunities should be there. But it will be difficult to replace the defense’s “engine,” as Schwartz often called Graham. On many recent occasions, if the veteran end made an early stop in the backfield, the unit would roll.

Just two weeks ago, the Falcons drove inside the Eagles 10 on their opening drive. But Graham had two run tackles, including this one for a loss, that helped keep Atlanta out of the end zone.

There are plenty of candidates to fill that energy void, but so few can deliver when it matters most.