The Eagles plan to sign defensive tackle Haloti Ngata and linebacker Corey Nelson after free agency opens Wednesday afternoon, according to league sources, adding to the Eagles' defensive depth and showing their commitment to reshape the roster even while tight on salary cap space.

Both players intend to sign one-year deals. ESPN first reported the additions. They are allowed to sign when the new league year begins at 4 p.m. on Wednesday, at which point the Eagles can also make official their trade for defensive end Michael Bennett with Seattle and the swap of wide receiver Torrey Smith for Carolina cornerback Darryl Worley.

The Eagles must be compliant with the salary cap, too, and they made big strides to do so Tuesday by agreeing to a restructured contract with Pro Bowl right tackle Lane Johnson, according to a league source. The Eagles will open about $7.5 million in salary cap space by converting a sizable portion of Johnson's base salary and roster bonus into a fully guaranteed signing bonus. Johnson will make the same amount of money, but the cap charge will be spread out over the last three years of Johnson's contract. The Eagles also released veteran tight end Brent Celek to save $4 million of salary cap space, saw tight end Trey Burton reach a deal with Chicago, and also prepared to say farewell to defensive tackle Beau Allen.

They found Allen's replacement in Ngata, a 34-year-old, five-time Pro Bowler. Although Ngata is not the same player who was twice named an all-pro while starring for Baltimore from 2006 to 2014 before joining the Detroit Lions for the past two seasons, he remains a big, talented defensive lineman who will take Allen's spot as the third defensive tackle in the Eagles' rotation behind Fletcher Cox and Tim Jernigan. Ngata's 2017 season was limited to five games because of an elbow injury, after which his effect on the Lions defense was most witnessed. The Lions allowed 55 more rushing yards per game after Ngata's injury, and he now takes that run-stopping ability to the NFL's top-ranked rush defense. Ngata was a nose tackle in Baltimore's 3-4 defensive scheme at 6-foot-4 and 345 pounds, but he played in a 4-3 defense with the Lions.

Ngata's been one of the NFL's top defensive players during the past decade, so it doesn't take much research to learn about him. But the Eagles are well-sourced in their building because vice president of player personnel Joe Douglas and his top assistant Andy Weidl were both in Baltimore during Ngata's time with the Ravens.

Similar to Ngata, Nelson was limited to five games in Denver last season because of an elbow injury. Nelson, 25, comes to Philadelphia with far less prestige than Ngata, although he could take on a role with the Eagles linebackers and will likely be needed on special teams. The 6-foot-1, 226-pound Nelson started five games since arriving in Denver as a seventh-round pick in 2014, but he was a key special teams player with increasing defensive responsibilities. The Denver Post reported that the Broncos were willing to match the Eagles' contract offer to keep Nelson, but Nelson sought a bigger role. That could come with the Eagles, who have uncertainty at linebacker with Nigel Bradham hitting the open market and Jordan Hicks recovering from a torn Achilles tendon.

Nelson totaled 104 career tackles along with six pass deflections and a sack. He took 44 defensive snaps last season before the injury. With 18 career special teams tackles, Nelson will be part of Eagles coach Doug Pederson's stated desire to upgrade the special teams this offseason. That unit took a hit with Burton's defection.

Both Ngata and Nelson arrive in Philadelphia sharing something in common with their new teammates: They both won Super Bowl rings. They bring that experience to one of the NFL's best rosters, for which they'll both be needed to fill roles of departed players.

There will be more players leaving – and likely more arriving – once the league year begins at 4 p.m. on Wednesday.

Staff writer Jeff McLane contributed to this report.