Green Bay Packers defensive coordinator Dom Capers, who has been with the team since 2009, is not expected to return next season, league sources told ESPN's Adam Schefter.
This would be the most significant of the offseason changes to Green Bay's defensive coaching staff.
After the Packers' 35-11 loss to the Detroit Lions on Sunday, coach Mike McCarthy would not address any questions about Capers' future.
"Let me say this, I'll answer questions about Packers vs. the Lions today, OK?" McCarthy said. "I get where we're at this point of the season. I haven't been in this position for a number of years, but I'm here to answer questions about the game, so let's not waste each other's time."
Capers, 67, is coming to the end of his ninth season in charge of the Packers' defense. It's the longest he's spent in any NFL job since he broke into the league with the New Orleans Saints in 1986.
He was twice a head coach, both with expansion teams (the Carolina Panthers from 1995 to '98, and the Houston Texans from 2002 to 2005), and was fired from both jobs.
Capers addressed speculation over his job security earlier this week by saying "my plans are from week to week in this business."
"One thing I've learned through a long career is you don't want to spend any time in this business concerning yourself with things that you don't have any control over, you know? You put the blinders on, you go to work, you try to be consistent in the way you do things and try to get guys ready to play," Capers said.
The Packers' defense will finish outside the top 15 in the league rankings for the sixth time in seven years. If the Packers don't improve from their 22nd overall defensive ranking entering Sunday's action, it will mark the fourth time in that stretch in which they've finished in the bottom third of the NFL (including a dead-last ranking in 2011).
Capers hasn't fielded a defense ranked in the top 10 since the Super Bowl season of 2010, when it was fifth.
ESPN's Rob Demovsky contributed to this report.