The Philadelphia Eagles have fired defensive coordinator Juan Castillo and have promoted secondary coach Todd Bowles to the post.
The move comes just two days after the Eagles blew a 10-point lead late in the fourth quarter and dropped a 26-23 overtime decision against Detroit.
Eagles head coach Andy Reid indicated on Monday that changes could be coming with the team just 3-3 heading into their bye week.
"We're six games into the season and average isn't good enough," said Reid. "I know the potential of our team and insist on maximizing it."
Castillo came under fire last year in his first season in charge of the defense after 13 years as the Eagles' offensive line coach. Reid stuck with Castillo despite widespread speculation of a potential change in the wake of an 8-8 season.
"I want to make it clear that I have nothing but the ultimate respect for Juan Castillo as a coach and as a person," Reid added. "He's one of the finest football coaches that I have ever worked with. He has served this organization extremely well for 18 years and letting him go was a difficult decision. I know he will continue to be a successful coach in this league and wish he and his family nothing but the best."
Reid's job security is also on the line this season. Owner Jeffrey Lurie had indicated during the summer that another .500 mark would probably force some major changes within the organization.
Bowles, meanwhile, was in his first season as Philadelphia's secondary coach. He joined the team in January after spending four seasons with the Miami Dolphins, including the final three games of the 2011 campaign as interim head coach.
The Temple product posted a 2-1 record last December with the Dolphins after Tony Sparano was fired and was considered for the full-time position that went to Joe Philbin.
Bowles has also been a secondary coach with Dallas, Cleveland and the New York Jets in 13 seasons as an NFL assistant.