"Have some personal pride. Have a freaking sense of urgency," Nagy told reporters Monday. "Yesterday was flat-out embarrassing."
"You better have some stinkin' fire," the coach added. "Enough is enough."
Chicago began the season 5-1 but has now lost five in a row following the Week 12 defeat.
The Bears turned the ball over three times against the Packers and trailed 41-10 in the fourth quarter before making the final score more respectable.
"S--t embarrassing," wide receiver Anthony Miller tweeted after the game.
There is still time for Chicago to turn around the season, with its next four opponents having losing records. Four of the team's six losses were also decided by just one possession, providing belief small changes could lead to wins.
It's still clear Nagy isn't happy with the team's effort Sunday and wants to see better over the last five weeks.