The 28-year-old prevented Brugge captain Hans Vanaken from taking the spot-kick with PSG leading 1-0 in the 76th minute on Wednesday, before seeing his effort saved by Keylor Navas as the Belgians went on to lose in Paris.
Coach Philippe Clement confirmed on Friday that Diagne would be punished.
"He will not appear in the squad for Antwerp on Sunday and I will decide in the coming weeks or months about a possible return to the team," said Clement, who gesticulated wildly at Diagne to give Vanaken the ball.
"There will also be a very heavy financial penalty."
Diagne has scored four goals for Brugge since signing on loan from Galatasaray in the close season.
Brugge sit third in Champions League Group A, 10 points behind leaders PSG, and will need to win their final two games against Galatasaray and Real Madrid to have any chance of reaching the last 16.