Stade Francais' win over Toulon in France's Top 14 on Sunday was marred by a fracas which saw a brother of one of the players run on to the pitch to get involved.
Home side Stade, who won the match 37-10, are facing a big fine and a possible stadium ban for failing to control the crowd.
Stade flanker Sekou Malacou clashed with All Black World Cup-winning wing Julian Savea, sparking a brawl involving virtually every player on the pitch.
Both players were eventually yellow carded but not before the France international's brother got involved.
He ran on to the pitch holding a flag in the pink colours of Stade. With his brother in the middle of the huge brawl he was not able to get at Savea - though he may have thought twice seeing the size of some of the players close up.