The Ligue 1 game between Montpellier and Clermont on Sunday was abandoned in injury time after visiting goalkeeper Mory Diaw was targeted by a firecracker thrown from the stands and had to be stretchered off.
Television pictures showed a firecracker landing next to the Clermont goalkeeper's feet and exploding with a loud bang, just as the match was entering stoppage time.
A clearly stunned Diaw went down and needed treatment before being carried off, and the game was halted before being abandoned following a crisis meeting.
"The doctor who examined the Clermont goalkeeper certified that he was not in a condition to return to the field. The match is therefore halted definitively," referee Florent Batta told media at the Stade de la Mosson.
Montpellier were leading 4-2 and on course to win their first home game of the season until the incident, and now risk serious punishment from the French footballing authorities with the prospect of having to replay the game without their fans.