Detroit Lions defensive coordinator Kelvin Sheppard is under fire after his team has allowed 71 points in two games. Fans are already calling for his firing, and it is starting to become a topic in media and league circles as well.
If the team were to move on from Sheppard within the season, the most logical name to step in during the year would be Assistant Head Coach and Safeties Coach Jim O’Neil.
John Maakaron of Lions OnSI pointed to O’Neil as one of his most likely Sheppard replacements.
“Detroit’s assistant head coach/safeties coach helped to develop Brian Branch and Kerby Joseph into one of the top safety duos in the league,” wrote Maakaron. “He has previous experience as the defensive coordinator of the Browns and 49ers. He had more success with the AFC North squad, as he only lasted one season in San Francisco.”
O’Neil also interviewed for the 49ers defensive coordinator job in 2025. He was the 49ers coordinator in 2016, before Kyle Shanahan was hired. He was almost given a second chance in San Francisco with Shanahan last offseason.
So, the Lions might have to decide whether to promote him or watch him get hired somewhere else.
Detroit Lions Have In-House Defensive Coordinator Option to Replace Kelvin Sheppard
Dave Birkett of the Detroit Free Press noted that he expects Sheppard to get a few more weeks as coordinator before his seat gets a bit hotter. However, he also noted O’Neil as one of the most likely candidates to step in if things continue to fall apart at this rate.
“If you’re talking potential in-season replacements should it ever get to that, safeties coach Jim O’Neil has previous coordinator experience, and secondary coach Deshea Townsend interviewed for the San Francisco 49ers DC job in January,” wrote Birkett.
So, it is not just one person linking the potential promotion. Of course, the Lions have not fired Sheppard yet. If they did, an in-house replacement would make the most of the season. So, at the very least, O’Neil might get a chance to close out the year.
Lions are High on Jim O’Neil
O’Neil has been in the NFL since 2009. He got his first chance as a quality control coach in 2009 with the New York Jets. He jumped to assistant defensive backs coach from 2010 through 2012.
In 2013, he moved to the Buffalo Bills as their linebackers coach. That last year, he got his first chance as defensive coordinator in 2014. He lasted two years before getting a chance as the 49ers’ coordinator in 2016.
He was out of the NFL in 2017 and returned as a senior defensive assistant with the Oakland Raiders in 2018. He was the defensive backs coach from 2019 through 2020 before being the Northwestern defensive coordinator in 2021 and 2022.
In 2024, he joined the Lions as an assistant. By 2025, he was the safeties coach, and this is his first year as the Assistant head coach. His rise suggests he could be a serious look.
Lions In-House Option Emerging as Kelvin Sheppard Replacement