Lyon's match with Toulouse was gripped by concern for winger Martin Terrier, who was stretchered off after collapsing during the game.
The 22-year-old went down off the ball in the 26th minute, after he was seen bending forward, before falling backwards to the turf where he then lie motionless.
His fellow Lyon teammates and the club's medical staff moved swiftly to help the Frenchman.
NBC report Terrier was unconcious, before waking suddenly and having some form of spasm after being turned onto his side.
Lyon forward Moussa Dembele was among those clearly worried about Terrier's health as he was removed from the field on a stretcher.
The club then released a statement at half-time which allayed fears regarding Terrier, and claimed he had suffered a Vasovagal syncope.
This causes a sudden loss of blood pressure and heart rate, resulting in the sufferer fainting.
Lyon tweeted: "Martin Terrier was the victim earlier of a fainting incident; our player is better and has regained consciousness."
It is not known what led Terrier to faint, but it is usually as a reaction to an emotionally distressing incident which acts as a stimuli triggering a nerve in the brain to respond.
Terrier was seen to be breathing heavily in the immediate aftermath of the incident, with one journalist suggesting he had suffered a fit.
Fansided reporter Matthew Ciavarella wrote on Twitter: "Hope everything is ok with Martin Terrier. He had some sort of fit on the pitch and just collapsed. The medics had to rush on the pitch so that he wouldn't swallow his tongue."
The match resumed once Terrier had been replaced by debutant Karl Toko Ekambi, with Lyon going on to win the game 3-0.
Terrier is a product of Lyion's academy, and has been a regular performer for the Ligue 1 club this season - making 16 appearances.
He is reported to be recovering well after the scare.
