Andre-Pierre Gignac scored a second-half hat-trick as France came from behind three times to beat South Africa 4-3 and keep their Olympic hopes alive.

Having lost their Group A opener, France looked to be heading out until former Marseille striker Gignac completed his treble from the penalty spot to level for a third time on 85 minutes, before Teji Savanier grabbed an injury-time winner.

Gignac, who currently plays for Tigres in Mexico, is now top scorer in Tokyo with four goals from two matches.

South Africa, whose hopes of qualifying have now been ended, led three times through second-half goals from Kobamelo Kodisang, Evidence Makgopa and Teboho Mokoena.

Group leaders Mexico face second-placed hosts Japan later on Sunday, with the top two progressing into the knockout rounds.