Fontang was in the 1987 round of 16 of the Orange Bowl International Championships. After a win over Byron Black, among others, he was clearly defeated by Nicolás Pereira in two sets. At the junior tournament of the French Open the following year, he was eliminated in the second round. 1990 was his first full year on the professional tour, in which he was on the ATP Challenger Tour with only moderate success . The following year was the best of his career. First he was in the final of the ATP tournament in San Marino , which he lost to Guillermo Pérez Roldán . In Palermo he defeated Andrij Medwedjew , Renzo Furlan and Jordi Arrese on the way to the final and he finally defeated Emilio Sánchez in three sets. He also won the title at the Challenger tournament in Merano with a final victory over Carlos Costa .
He could not repeat the successes of 1991. Once again he was in the final of a Challenger tournament, but lost to Johan van Herck in Ostend . In 1999 he ended his career; but he returned again between 2004 and 2006. In his appearances in lower-class futures he failed with one exception in the first round. He reached the highest ratings in the ATP world rankings in 1991 with position 59 in singles and 589 in doubles. His best result in a Grand Slam tournament was when he reached the second round of the French Open .
After his professional career, Fontang looked after Jérémy Chardy for twelve years . Vasek Pospisil then hired him as a trainer.
France
Palermo
Emilio Sánchez