The Seahawks’ roster is about to undergo some big changes.

Just as the Hawks likely lose Will Dissly for the season again, they are getting back Jarran Reed. Basically, they are trading one big loss on offense for one big addition on defense.

They also might soon add rookie guard Phil Haynes and/or veteran tight end Ed Dickson — who both could offer some useful depth.

Reed, finishing a perplexing six-game suspension, is ready to “clock in” and help a defensive front that has had trouble generating much pass rush all season.

After the Hawks’ 32-28 win in Cleveland, K.J. Wright was excited at the prospect of getting Reed back.

“Oh yeah!” Wright laughed on Q13. “Jarran Reed: That’s going to be fantastic. He’s my guy. To have him up front, he’s just the leader of the D-line. Pass-rush specialist. He takes up double-teams for us. It’s going to be really fun. I can’t wait for him to get back.”

They could use him. They barely touched Baker Mayfield on Sunday and still have not been able to get consistent pressure from a unit that includes newbies Jadeveon Clowney and Ziggy Ansah — although both of those guys have made some key takeaways early this season (including a fumble by Ansah in Cleveland).

Pete Carroll said he is not worried about it (which maybe is easier to say when you are 5-1). “We’re still searching to get it right. I’m not impatient about that. We’re still working at it. We’ll figure it out. We ain’t even halfway through this thing yet. We have a longs ways to go.”

Meanwhile, Haynes (sports hernia) will start practicing this week. The team will have three weeks to activate him or put him on injured reserve. The same goes for fellow rookie Demarcus Christmas, who seems less likely to find a spot on the 53.

Haynes showed promise during OTAs, but that was a long time ago. Who knows whether he will be ready to contribute to a banged-up line that lost Ethan Pocic and could use reinforcements? If so, he could replace Jordan Roos, who was called up as an emergency backup as the Hawks played without D.J. Fluker and Duane Brown this week.

With Dissly gone, Dickson could be a useful addition as well. But Carroll said last week that he was “concerned” about Dickson’s possible return from knee surgery. Carroll said “the race is on” for Dickson to be ready when he is eligible to come off IR, in Week 9. He is allowed to start practicing this week, if he’s ready. Carroll talked to him in the weight room Monday morning and told him he is counting on him to make it back.

At this point, the Hawks are going with two recent (though familiar) additions — Luke Willson and Jacob Hollister — replacing the traded Nick Vannett and Dissly.

Some fans are tossing out the idea of Seattle pursuing a trade for Tampa Bay’s O.J. Howard, but the Hawks likely will just go with Willson, Hollister and George Fant (who will resume his TE role once Duane Brown returns to the lineup).