With Beau Allen set to become a free agent, the Super Bowl champion Eagles were in the market for depth at defensive tackle. Joe Douglas, the Eagles' vice president of player personnel, is familiar with Ngata from their time together with the Baltimore Ravens. Douglas served as a scout in Baltimore from 2000 to 2015.
Allen, who specialized in stopping the run, played 41 percent of the defensive snaps in 2017 as part of an Eagles line rotation that included Fletcher Cox, Tim Jernigan and Destiny Vaeao. Defensive end Michael Bennett, recently acquired from the Seattle Seahawks, often moves inside on passing downs, so there will be a host of players vying for snaps. But line depth was huge for the Eagles last season; seven of their defensive linemen played at least 400 snaps, most in the NFL, per ESPN Stats & Information.
Also, Denver Broncos linebacker Corey Nelson intends to sign a 1-year deal with the Eagles, a source told ESPN's Josina Anderson.
Ngata, 34, spent the past three seasons with the Lions, who acquired him in 2015 in the wake of Ndamukong Suh signing with the Miami Dolphins. Ngata played 32 games for Detroit, making 53 tackles with six sacks.
He was a large part of Detroit's run defense the past three years and served as a mentor to younger defensive linemen, including A'Shawn Robinson and Akeem Spence. Ngata suffered a biceps injury against the Carolina Panthers in Week 5 of the 2017 season, which resulted in him going on injured reserve.
In January, Ngata told 97.1 FM in Detroit that he wanted to play in 2018. Before the 2017 season, Ngata went to the The Sports Neurology Clinic at the CORE Institute in Brighton, Michigan, for an examination before deciding to play.
"I don't want to have problems when I'm older. I want to be able to raise my kids and be able to play with them when they are older and still be able to beat them in wrestling matches and stuff when they are teenagers," Ngata said in 2017.
The No. 12 overall pick by the Ravens in the 2006 draft, Ngata spent nine years with Baltimore, being named AP first-team All-Pro twice and making five Pro Bowls. He also was a member of the Ravens' Super Bowl XLVII championship team.
Ngata has played in 167 games, making 498 tackles with 31.5 sacks, 6 forced fumbles, 5 fumble recoveries and 5 interceptions. He also has 27 career pass breakups.
ESPN's Tim McManus and Michael Rothstein contributed to this report.