Entering last season, members of the Washington Redskins’ defense figured their unit would be among the league’s best, and they were prepared to have to do the team’s heavy lifting last year, if needed, while the offense settled in with rookies starting at quarterback and tailback.

Things played out far differently. The defense struggled for much of the season while the offense thrived behind quarterback Robert Griffin III, the NFL’s offensive rookie of the year, and running back Alfred Morris, who set a single-season team rushing record. The defense did manage to regroup in time to contribute to the Redskins’ seven-game winning streak that produced an NFC East crown.

But as the Redskins prepare to try to defend that division title and go deeper into the playoffs this season, those on the team’s defense know that more is needed from them this time around.

“I think we were fifth in the league in rushing and third in turnovers” last season, defensive coordinator Jim Haslett said during training camp. “We’ve got to keep those numbers up. Obviously we wanted to create turnovers. But we’ve got to do a better job in the pass game than we did last year. We gave up too many big plays and didn’t do as well as we would have liked. I think that area, we will improve on and be much better. And then, we’ll have a better pass rush, also.”

As Haslett noted, not all was bad with the defense last season. The Redskins indeed ranked fifth in the league in run defense. They forced 31 turnovers and the team’s plus-17 turnover differential was third in the league. But there was plenty of bad, as the Redskins ranked 30th in the league in pass defense and 28th in total defense, based on yards allowed.

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Defensive end Adam Carriker and outside linebacker Brian Orakpo suffered season-ending injuries in the second game. Safety Brandon Meriweather played only one game all season because of a series of knee injuries. The pass rush suffered without Orakpo, as fellow outside linebacker Ryan Kerrigan had too little help. The secondary struggled minus Meriweather, a versatile playmaker who resembled a difference-maker in the one game he did play against the Philadelphia Eagles.

The defense does take pride in its perseverance and late-season improvement last year. Linebacker London Fletcher fought injuries all season but played on, as always, and was the NFC’s defensive player of the month in December.

“Last year we did have two different types of seasons,” Fletcher said in training camp. “I think obviously having some injuries and trying to figure out different roles for different guys, that factored in. The coaching staff finally realized, ‘Okay, I’ve got these guys. What are their strengths? What are their weaknesses? Let’s play to these guys’ strengths.’ I think we really just locked in better as a football team collectively. The offense played great. The defense played great. The special teams played great.”

The Redskins attempted to upgrade the secondary in the NFL draft by choosing cornerback David Amerson in the second round and two safeties thereafter, fourth-rounder Phillip Thomas and sixth-rounder Bacarri Rambo. Thomas suffered a season-ending Lisfranc foot injury during the preseason, but Amerson and Rambo are to have key roles. Rambo is penciled in to start at safety alongside Meriweather.

The depth of the defense will be tested early on. Carriker is on the physically unable to perform list after having a third surgery for his torn quadriceps tendon. Jarvis Jenkins, Carriker’s replacement in the starting lineup at defensive end, and reserve outside linebacker Rob Jackson are suspended for the first four games of the season for violations of the NFL’s policy on banned performance-enhancing substances. Reserve linebacker Keenan Robinson had his season ended before it even started, suffering a torn pectoral muscle during the opening practice of training camp. Backup cornerback Richard Crawford suffered a season-ending knee injury during the preseason.

But the Redskins say they’re confident in the players who will fill in. Nick Barnett, a linebacker entering his 11th season, was signed after Robinson’s injury. Kedric Golston and Chris Baker become prominent with Jenkins suspended. Rookie linebacker Brandon Jenkins joins the team’s pass-rushing packages.

Much of the rest of last season’s defense stayed intact. Last season’s starting cornerbacks remain in the fold, with DeAngelo Hall re-signing after being released before free agency and Josh Wilson accepting a pay cut to stay. The Redskins are pinning their hopes for improvement largely on having Meriweather and Orakpo back. Orakpo is a two-time Pro Bowler who has 291 / 2 sacks in 49 career games.

“The defense as a whole will be uplifted even more with ’Rak being back,” Kerrigan said during camp. “Just what he brings to the table in terms of his versatility and his ability to play the run and play the pass and cover in pass coverage — he’s got the total package. He’s going to be huge for our team.”