Lyon's Europa League quarter-final meeting with Besiktas was delayed by 45 minutes after the throwing of projectiles and firecrackers forced fans onto the Parc OL pitch on Thursday night, reports The Telegraph.
Both sets of players had emerged to warm up when objects began to rain down from the stands, causing an unexpected postponement of the start of proceedings in France.
It followed fighting among rival French and Turkish fans earlier in the city.
The match was expected to kick off at 8.05pm BST, but Uefa spokesman Pedro Pinto tweeted that there would be a delay due to "crowd disturbances", and the match did not begin until 8.50pm BST.
With an image of supporters entering the field of play, Lyon posted a tweet reading: "Projectiles and firecrackers thrown from the tops of the stands have forced fans to take refuge on the pitch."
At 8.16pm BST, after all members of the public had left the playing surface, Lyon tweeted that a revised start time would be announced "in several minutes", later saying a second warm-up was imminent.
Pinto then tweeted: "Authorities at Stade de Lyon confirm @EuropaLeague match between @OL and @Besiktas can take place. Kick off expected soon."
Lyon and Besiktas, the Turkish champions, finally kicked a ball at 9.50pm, local time.