Matt Patricia has hired Eagles defensive backs coach Cory Undlin as the Lions' new defensive coordinator, according to Field Yates of ESPN.
Patricia and Undlin were entry-level assistant coaches on Bill Belichick's staff in 2004 and have remained close.
Undlin replaces Paul Pasqualoni, who informed the Lions earlier this month that he was leaving coaching. Pasqualoni was head coach when Donovan McNabb was at Syracuse. McNabb, of course, quarterbacked the Eagles when they faced Undlin, Patricia and the 2004 Patriots in the Super Bowl.
Chip Kelly hired Undlin as the Eagles' defensive backs coach after the 2014 season to replace John Lovett, who had been with the team for two years, and Doug Pederson kept him in the same role when he replaced Kelly after the 2015 season.
The Eagles have allowed the 10th-most passing yards in the NFL during Undlin's four years under Jim Schwartz, but opponents have thrown the third-most passes. Opposing quarterbacks had an 87.4 passer rating against the Eagles during that span, 12th-lowest in the league, and completed 62.1 percent of their passes, 8th-worst in the league.
During that four-year period, the Eagles allowed 44 pass plays of 40 yards or more, 5th-most in the league, and 18 TD passes of 40 yards or more, 4th-most in the league.
But the collection of cornerbacks Undlin has had to work with hasn't exactly been inspiring, and he deserves a ton of credit for holding things together over the last three years with a constantly rotating and changing lineup.
Some 15 different cornerbacks started at least one game for the Eagles over the last four years, and 19 played meaningful snaps in the regular season.
In 2017, the Eagles won the Super Bowl with Jalen Mills and Ronald Darby starting at cornerback and Patrick Robinson in the slot.
What is Undlin's role in the slow or non-existent development of 2nd-round draft pick Sidney Jones and 3rd-round pick Rasul Douglas? It's impossible to say now, but generally speaking, it appears Undlin has gotten the most out of a collection of late-round picks, street free agents, undrafted players and other teams' castoffs at cornerback.
Malcolm Jenkins, who hadn't made a Pro Bowl in his first six seasons in the NFL, made three in five years playing under Undlin.
Dino Vasso is currently the Eagles' assistant secondary coach and could be a candidate for the opening.
Vasso, who began his coaching career as an intern at Temple in 2011, spent three years as an entry-level assistant under Andy Reid with the Chiefs and followed Pederson to the Eagles after the 2015 season.
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