The 22-year-old opened the scoring with his first league goal of the season before producing the controversial celebration.
Advertisement
Advertisement
Coulibaly later apologised, having explained at half-time that the gesture was a tribute to a friend who had asked him to perform it.
His actions mirror those of teammate Paris Brunner, who recently received a four-match suspension, including two mandatory matches, from the French Professional Football League's disciplinary committee for a similar celebration.
Monaco manager Filipe Luis previously defended Brunner while stressing the club's commitment to preventing such incidents.
Coulibaly could now face a similar punishment if disciplinary proceedings are opened.