A woman referee was hurt and had to leave the field after being knocked down during a friendly between French club Metz and Dutch side Fortuna Sittard.
Mathilde Demoncay is said to have suffered a concussion, external after being knocked over while trying to break up a scuffle between players.
The flashpoint came in the 40th minute when two opponents squared up following a shirt pull, prompting others to rush in.
Demoncay, attempting to intervene, fell heavily to the ground.
She remained on the pitch for several minutes, clutching her arm, as assistant referees, security staff and medics entered to restore order and assess her.
The 26-year-old resumed as an assistant referee after play restarted but left at half-time, with another assistant taking over.
Metz won 3-1.