LOS ANGELES — D’Anton Lynn was born into the NFL, his father Anthony Lynn the former head coach of the Chargers. But his introduction to coaching in the NFL, as D’Anton Lynn once said, was Rex Ryan. A slew of influences, since Lynn started in the NFL as an intern with Ryan’s Jets in 2014, have left their mark, like former Chargers defensive coordinator Gus Bradley and current Seahawks head coach Mike Macdonald.

But it “all comes back to Rex,” Lynn said, upon the USC defensive coordinator’s second time speaking with the media in February.

And faced with a key vacancy on a new-look defensive staff, USC and Lynn have turned back to that Ryan coaching tree – just not Rex. On Saturday morning, USC announced it had hired longtime NFL coordinator and assistant Rob Ryan — Rex’s brother — as its newest linebackers coach, also earning the title of assistant head coach for defense.

“With over two decades of NFL experience, he will immediately bolster our staff as we continue our climb here at USC,” coach Lincoln Riley said in a statement announcing Rob Ryan’s hire.

In December 2023, upon nabbing Lynn from UCLA, Riley said the program’s “north star” was to build the best defensive staff in America. Just over a year later, the amount of pro-level pedigree on USC’s staff can rival most anyone across the country. Lynn grew for nearly a decade in the NFL, and coached the safeties on a formidable Baltimore Ravens defense before coming to UCLA. Defensive line coach Eric Henderson won a Super Bowl with the Rams.

Enter the fiery Ryan, once a coordinator for four NFL teams and a defensive mind who’s coached Pro Bowlers like New Orleans Saints defensive end Cameron Jordan and former Dallas Cowboys pass-rusher DeMarcus Ware.

It’s Ryan’s first collegiate job since a stint as Oklahoma State’s defensive coordinator from 1997-99. Since, he has coached the linebackers on multiple Super Bowl-winning Patriots teams, coordinated for the Raiders, Browns, Cowboys and Saints, and most recently served for three years as a senior defensive assistant for the Raiders.

Ryan brings immediate cohesion to Lynn’s staff and scheme. Ryan first crossed paths with Lynn under brother Rex’s staff with the Bills in 2016, when the future USC coordinator was a defensive assistant. They reunited for a year with the Ravens in 2021, Ryan the inside linebackers coach and Lynn the safeties coach.