The 2012 Baltimore Ravens fired embattled offensive coordinator Cam Cameron after they lost to Washington in overtime. They dropped to 9-4 on the season and were still in the driver’s seat to win the AFC North. Jim Caldwell replaced Cameron and they obviously won the Super Bowl, in large part due to Joe Flacco turning in one hell of a series of playoff performances.
I led with that paragraph because it shows that just because you’re winning most of your games and you’re leading your division does not mean you cannot shake up your coaching staff when things aren’t working.