Redskins linebacker Rob Jackson is almost finished serving his four-game suspension to open the season. (John McDonnell/The Washington Post)

Reserve linebacker Rob Jackson is about to have his four-game suspension for violating the league’s substance abuse policy expire, and he said Thursday he’s eager to resume his normal activities with the Washington Redskins next week.

“I’m just happy that I did my time and I get to go back out there and play football,” Jackson said in the locker room at Redskins Park.

Jackson must sit out Sunday’s game at Oakland before his suspension ends. The Redskins have a bye after that, then resume play with an Oct. 13 game at Dallas.

“It’s been rough,” Jackson said. “The first couple weeks [were] rough. But …it went by fast. I still got to come out here and work out, see the guys, stay in shape, things like that. But I’ve got a couple more days and I’m back with the team on Monday.”

Jackson so far has watched the Redskins go winless while their defense has given up yards at a dizzying rate.

“It’s definitely frustrating,” he said. “I’m just excited to get back out there and to win. That’s most important.”

● Related: All suspensions news | Difference between Jackson, Jenkins punishments

Jackson said he speaks almost daily to defensive end Jarvis Jenkins, whose four-game  suspension for violating the NFL’s policy on banned performance-enhancing substances also is about to expire. Jenkins, unlike Jackson, has had to stay away from the team’s facilities under the terms of the drug policy under which he was suspended. Jackson said he hopes it won’t take him too long to regain his on-field sharpness.

“Hopefully it won’t be too hard and it won’t take me too long,” he said. “I have a whole week of practice with the team and a game plan. Hopefully I can knock the kinks out, if there’s any kinks, during that week.”

Have a Redskins question? E-mail Mike Jones at with the subject line “Mailbag question” for him to answer it in The Mailbag on Tuesday.

What’s ahead:

● The Redskins practice at 1 p.m. on Thursday. Both coordinators speak to reporters.

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