Lyon's Ligue 1 match against Marseille on Sunday was postponed after the away team's bus was stoned on its way to the Stade Velodrome.
It is the latest incident in French football's chronic issue with fan violence, and came on the same day France's most celebrated current player, Kylian Mbappe, goaded supporters of Brest in Paris Saint-Germain's 3-2 victory in Brittany.
Lyon coach Fabio Grosso's face was left bloodied and his assistant was also injured as the team bus was pelted with stones en route to the Velodrome, shattering several windows. A club source said Grosso had also been experiencing dizzy spells.
A crisis unit was set up to decide the fate of the match, with Lyon making clear their reluctance for the game to go ahead given the circumstances.
"Based on Lyon's wishes ... the decision was taken not to start the match," said referee Francois Letexier, adding that reports "have been forwarded to the relevant authorities who will decide what action to take".
Prime Video footage showed Grosso with a bandage on his head as he came out of the stadium's medical room.
A photo circulating on X, formerly Twitter, appeared to show Grosso lying on a stretcher with a cut above his left eye.
"These are completely unacceptable circumstances," said Marseille club president Pablo Longoria.
"My first thought is for Fabio Grosso, someone I respect and have known for a long time. I went to see him as soon as I arrived at the stadium, I saw how he was."
A second bus containing Lyon supporters was also attacked with stones and the windows damaged, a local police source told AFP.
"These images are revolting. Seeing the stoned bus like that, the bloody face of Fabio Grosso ... These are unacceptable acts which go against the very values of football and sport," French sports minister Amelie Oudea-Castera told AFP.
"I hope that the investigation will be carried out quickly, that the perpetrators are found and they are severely punished."
Earlier on Sunday, Mbappe struck a late winner at Brest and then riled the opposition and home supporters as he celebrated the goal, pressing his finger to his lips and gesturing to the crowd.
The France captain was booked over the incident and said on social media his actions were due to insults aimed by the crowd at one of his teammates, later confirmed to AFP to be Achraf Hakimi.
Morocco international Hakimi was given preliminary charges of rape in March, accusations the player strongly denies.
"Well of course and I should have even sang with them when they insulted my teammate," Mbappe wrote in a sarcastic response to a tweet critical of his behaviour.
"Some have really never set foot on a football field no matter the level."
PSG midfielder Danilo Pereira said the treatment of Hakimi by home fans had made Mbappe "angry", but Brest coach Eric Roy said he was "a bit surprised" by the reaction from the striker.
"It's a pretty healthy atmosphere. So of course you can always be jeered. When you have the match you've had, you've scored two goals, it's a bit ridiculous. You should be above all that," said Roy.
"It's a shame that tarnished the end of the match."
