Guingamp have been relegated from Ligue 1 after Sunday’s 1-1 draw away to Rennes.
The fate of Jocelyn Gourvennec’s side looked to be sealed when they were still trailing 1-0 to Ismaila Sarr’s early goal with three minutes remaining.
But Alexandre Mendy struck to give them hope, with referee Karim Abed then awarding Guingamp a penalty for handball in added time.
Marcus Thuram – son of World Cup winner Lilian – could not convert the penalty, though, as goalkeeper Tomas Koubek made the save.
Guingamp, who lost the Coupe de la Ligue final to Strasbourg on penalties in March, therefore cannot climb out of the relegation zone.
It is the third time they have been relegated from Ligue 1 and the first time they have fallen out of the top flight since 2003-04.
With two rounds of games to go, Dijon occupy 19th place in the table with Caen two points above them.
Monaco are only above the relegation play-off place on goal difference.