5 fresh candidates to replace Aaron Glenn as Lions defensive coordinator

Now that Aaron Glenn actually needs to be replaced as Lions' defensive coordinator, here's a fresh a list of candidates to do so.

Junfu Han / USA TODAY NETWORK via Imagn Images
3 of 3

2. Lions defensive assistant Jim O'Neil

O'Neil has spent the last two seasons as a defensive assistant with the Lions, with focus on working with the safeties that taps into his history as a defensive backs coach. The work done by Kerby Joseph, Brian Branch and Ifeatu Melifonwu (for his brief fully healthy stretch late in the 2023 season) stand as prominent marks on his resume.

But O'Neil also has some experience as a defensive coordinator. He was the defensive coordinator at Northwestern for two seasons before coming to the Lions, and he had stints in the role for the Cleveland Browns (2014-2015) and San Francisco 49ers (2016).

Experience and familiarity automatically puts O'Neil somewhere on the radar to replace Glenn in Detroit.

1. Lions linebackers coach Kelvin Sheppard

Sheppard is a rising star, and he would be an easy candidate to follow Glenn and be his defensive coordinator in New York. But it seems like Glenn is moving in the direction of having a more experienced defensive coordinator who has head coaching experience (namely Steve Wilks), leaving Sheppard as the easy top candidate to replace Glenn in Detroit.

Glenn talked openly about grooming Sheppard for his eventual future as a defensive coordinator

"And having Shep there with me, he’s been there from the beginning, and he knows exactly how I think – exactly,” Glenn said last month, via Ben Raven of MLive. “And that’s a guy that I’ve been actually mentoring to be in the DC role at some point."

In light of Glenn's looming departure (which has now of course happened), Jordan Schultz of FOX Sports noted Sheppard as a "hot name" to land a defensive coordinator role.

"If Aaron Glenn lands a head coaching job, keep an eye on #Lions LBs coach Kelvin Sheppard as a hot name for landing a defensive coordinator role."

"Sheppard, who played eight NFL seasons, has a sterling reputation inside the Detroit building and across the league as a whole."

Note how Schultz's report did not get directly specific about Sheppard replacing Glenn as Lions defensive coordinator, but that he'd generally be a candidate for a defensive coordinator job. So Campbell may need to move quickly to keep Sheppard in the fold.

Schedule