Kyle Larson was handed a stiff L1 penalty on Tuesday following Saturday's KC Masterpiece 400 at Kansas Speedway.
NASCAR announced Tuesday afternoon that during teardown they found the N0. 42 rear window was not flush with the rear deck lid and the rear window support braces were not keeping the glass of the rear window rigid in all directions.
Larson was fined 20 points, crew chief Chad Johnston has also been fined $50,000 and car chief David Bryant has been suspended for two races.
Larson said following Saturday's race that the windshield looked the way that it did because of contact with Ryan Blaney on lap 248.
Ganassi has not yet announced a replacement car chief and will not appeal Tuesday's penalties.
“Although all parties agree that the infraction was unintentional and the result of contact, we will not appeal the penalty so that we can focus our energy on the All-Star race and the Coca-Cola 600," Chip Ganassi Racing said in a statement.
Tuesday's penalty that was handed down to team NO. 42 wasn't the first rear-window issue NASCAR has had to face with teams this season. In March, Kevin Harvick was handed the L1 penalty for two violations within the rear-window area.
Chase Elliott and Clint Bowyer have also been handed down penalties from NASCAR this season for a lack of rigidity in the rear-window area.