SEATTLE -- Upgrading their pass rush already figured to be on the Seattle Seahawks' offseason to-do list with that unit producing inconsistently in 2017 and facing questions about whether some of its members will be back.

That becomes an even bigger need with ESPN's Adam Schefter reporting Wednesday that Seattle has agreed to trade defensive end Michael Bennett to the Eagles. It might end up being the Seahawks' biggest need depending on what other major shake-ups they make to their roster in general and their secondary in particular.

In sending Bennett to Philadelphia, the Seahawks are parting with a still-effective pass-rusher even if they feel that Bennett, who turns 33 in November and dealt with an assortment of injuries last season, is on the decline. He had 8.5 sacks last season, second on the team behind Frank Clark's nine, and again led all Seattle defensive linemen in playing time by a wide margin.

That group underwhelmed in 2017 based on preseason expectations. There were games in which the Seahawks' pass rush was problematically absent, most notably a December loss to the Jacksonville Jaguars when Seattle failed to sack Blake Bortles and hit him only once. On the season, Seattle generated pressure on 27.9 percent of opposing quarterbacks' dropbacks, according to ESPN Stats & Information. That 27.9 percent ranked 18th in the NFL, while Seattle's 39 sacks were tied for 13th.

Each figure represented a slight drop-off from 2016, which is not what anyone expected given how stacked Seattle's pass rush became following the addition of Sheldon Richardson.

Along with losing Bennett, that group likely won't have Cliff Avril, his fellow Pro Bowl defensive end whose football future is in jeopardy because of a neck injury he suffered in early October. There's also a good chance it won't have Richardson, who's headed toward free agency and could price himself out of Seattle. The Seahawks declined to use the franchise tag on Richardson, signaling they don't think he's worth the $14 million that it would have cost to do so, but Richardson could conceivably find a deal worth that much on average on the open market.

Remember that Seattle traded for Richardson before the start of last season when it became clear that top draft pick Malik McDowell would be unavailable for much of his rookie season after injuring himself in an ATV accident. There's been nothing to suggest McDowell is any closer to being cleared to play -- all of which shows how much help Seattle might need along its defensive line.

Clark is entering the final year of his rookie deal while Dion Jordan is a restricted free agent who is expected to be tendered. Jordan gave Seattle four sacks in five games last season, and Clark has double-digit sack potential. That's a good start, but the Seahawks need much more, particularly if they don't have the familiar stars in the Legion of Boom that give pass-rushers that extra split second to get to the quarterback.

The Seahawks cleared only $2.2 million in 2018 cap space by trading Bennett. He'll count more than twice that amount -- around $5.2 million -- in dead money against Seattle's 2018 cap. Such minimal cap relief strongly suggests Seattle's decision to move on from Bennett was about more than just his production versus his price tag. Perhaps part of that decision was the Seahawks felt their locker room, particularly their young defensive line room, needed a new leadership voice other than Bennett, who was one of the team's longest-tenured players.

Seattle picked up some needed draft capital by trading Bennett, adding a fifth-round pick (plus receiver Marcus Johnson) while giving the Eagles a seventh. Seattle has eight picks in all: a first, a fourth, four fifths and two sevenths. The Seahawks will need to hit on those picks now more than ever if they substantially retool their roster.

That's increasingly likely with Richard Sherman's status up in the air. A report from the NFL Network that the cornerback has said his goodbyes to teammates comes days after trade speculation involving free safety Earl Thomas heated up at the scouting combine.

Couple that with the uncertain future of strong safety Kam Chancellor, who's also dealing with a career-threatening neck injury, and the Seahawks' historically good defense could look significantly different next season.

For now, though, what's clear is that Seattle's pass rush just became an even bigger need.