Defensive coordinator Greg Manusky and a healthy Junior Galette are two new pieces to the Redskins’ revamped defense. (Photo by John McDonnell / The Washington Post)

The Washington Redskins will finally unveil their revamped defense, featuring a new defensive coordinator, a new scheme and six new starters, on Sunday in the season opener against the Philadelphia Eagles. The Redskins’ expectation is the unit will show immediate improvement, though it remains unclear how it will fare.

“We hope it comes together,” Coach Jay Gruden said. “It has to, we don’t have a lot of choice. Philadelphia’s coming to town on Sunday, so we better be ready.”

The Redskins are hoping the defense will gel in Greg Manusky’s first game as defensive coordinator, although reality would suggest it will take some time for all of the new pieces to come together. Washington has only had three preseason games to gauge how good its first defensive unit can be, and it allowed touchdowns on the first series against the Green Bay Packers and Cincinnati Bengals in limited action. Assessing the defense’s readiness is complicated because the schemes it employed during the preseason were limited; the regular season promises to feature more aggressive play-calling.

The defense has yet to display the cohesiveness it will need during the regular season, but Manusky conveyed a sense of urgency for it to come together at FedEx Field on Sunday.

“I think it’s a little bit ASAP,” Manusky said. “I think the sooner the better. I think the guys have been working hard in the OTAs [organized team activities] and training camp and in the preseason games. I know they didn’t get a lot of reps as a first unit, but overall, I think with the practices that we’ve had and with the prep time we’ve had in this coming week for Philly, I’m excited about what’s going to happen this weekend.”

Gruden has yet to establish a formidable defense in his three seasons as head coach, despite two years with winning records. Gruden’s tenure started with defensive coordinator Jim Haslett, who was ousted after 2014 for running a defense that allowed 438 points. The Redskins improved in points allowed during the following two seasons under Joe Barry, finishing 17th and 19th in the NFL, but they struggled to get off the field last year with the worst third down defense in the league.

Gruden feels optimistic about his defense heading into this season because of its energy level and communication. The free agent acquisition of safety D.J. Swearinger, who was named defensive captain this week, has been a significant reason for the improvement in both areas compared to last season, along with inside linebackers Zach Brown and Mason Foster.

“It just feels that way,” Gruden said of the defense’s energy. “We’ll see on Sunday, but I imagine — I hope — the energy is different. I just think we added some new pieces that will bring us to a different level.”

While Swearinger, Brown and a healthy Junior Galette will serve as upgrades among the linebacker corps and secondary, Washington’s defensive line remains a significant uncertainty. Its most talented player is arguably the Redskins’ first round draft pick Jonathan Allen, who Gruden hopes can use his athleticism to become a game-changing interior lineman similar to Eagles defensive tackle Fletcher Cox. But the Redskins will need production from free agent pickups Terrell McClain and Stacy McGee, while using Ziggy Hood at nose tackle after Phil Taylor Sr. was placed on injured reserve during the preseason.

Hood had to learn the position on the fly last year, when Washington lacked a true nose tackle on its roster. The team faced the same predicament again this year, except Hood feels more prepared after practicing at both defensive end and nose tackle during the offseason. His objective is to free up linebackers by controlling his assigned offensive lineman while also being in a position to make plays

“Keep their guys off our guys,” Hood said. “Not only that, but put yourself in better position to make plays as well. We’re attacking, playing blocks and stuff like that. We’re not allowing anyone to run up free to the [linebackers].”

This defense will be a work in progress, but it’s a results-based league. Washington will have to find the fine line between being urgent, yet patient, as the process plays out over the course of 16 games.

“It’s a continuous climb,” Foster said. “You want to always keep getting better. If you stay the same, you [are going to] get beat. You gotta keep getting better. … It’s a long season, but we definitely want to start off hot. We definitely want to come out the gate and let people know what we’re here to do this year. You’re gonna set the bar high, and reach for it.”

Read more:

Thursday’s takeaways: Run game, Chris Thompson’s new deal, starting nose tackle

Bog: Kirk Cousins has a nook at Redskins Park, and he loves it

Scouting reports and grades for the Redskins’ projected starting lineup

Breaking down the Redskins’ schedule game by game

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