Joe Philbin has been named interim head coach and will remain as the team's offensive coordinator.
"The 2018 season has not lived up to the expectations and standards of the Green Bay Packers. As a result, I made the difficult decision to relieve Mike McCarthy of his role as head coach, effective immediately," Packers president and CEO Mark Murphy said. "Mike has been a terrific head coach and leader of the Packers for 13 seasons, during which time we experienced a great deal of success on and off the field.
"We want to thank Mike, his wife, Jessica, and the rest of the McCarthy family for all that they have done for the Packers and the Green Bay and Wisconsin communities. We will immediately begin the process of selecting the next head coach of the Green Bay Packers."
Murphy will hold a press conference on Monday afternoon.
Following the defeat but prior to the announcement, McCarthy admitted he'd never been in the position of being so far from playoff contention at this point in the season.
"I mean, I’ve never been in this spot," McCarthy said, according to Pro Football Talk's Josh Alper. "I'm not going to act like I know what the hell I’m going to do tomorrow when they get in here. So, we’re going to do what we always do, we’re going to represent the Packers the right way, I know that. Other than that, we’ll focus on what’s in front of us."
The 55-year-old began his tenure as Packers head coach in 2006, posting a cumulative 125-77-2 record and winning the Super Bowl in 2011.
McCarthy was the second-longest tenured head coach in Packers history, behind only Hall of Famer Curly Lambeau (1921-1949).
Green Bay has slumped to a 4-7-1 record this season and is in serious danger of missing the playoffs for the second consecutive campaign.