(John McDonnell/The Washington Post)

The depth of the Washington Redskins’ defense will be tested, especially early in the season when defensive end Jarvis Jenkins and reserve linebacker Rob Jackson are serving four-game suspensions for violating the NFL’s policy on banned performance-enhancing substances.

The Redskins also lost reserve linebacker Keenan Robinson to a torn pectoral muscle suffered during the opening practice of training camp.

But defensive coordinator Jim Haslett is hopeful the unit is up to the task.

“Obviously not having Jarvis for the opener and Jackson for the opener, those are setbacks,” Haslett said. “That’s kind of [like] guys get hurt and missing four games. So you adjust. We went through it last year. I feel good about Kedric [Golston] playing. Chris Baker has moved to end, playing a lot of end. You know, he played nose [tackle] for us last year. He’s done a nice job. He’s athletic. Phillip Merling has done a nice job for us. So we feel that we’ve got enough depth that if something happens, we’ll be in good shape.”

Haslett said he’s hopeful the defense will continue to play well against the run and generate turnovers the way it did last season while improving its performance against the pass. The Redskins ranked 30th in the league in pass defense last season.

“Obviously we wanted to create turnovers,” Haslett said. “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.”

Have a Redskins question? E-mail Mike Jones at mike.jones@washpost.com with the subject line “Mailbag question” for him to answer it in The Mailbag.

What’s ahead:

● Washington hosts the Pittsburgh Steelers Monday at 8 p.m. in their first game of the preseason at FedEx Field.

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