Under Fontang's guidance, Auger-Aliassime won nine ATP singles titles and climbed to a career-high ranking of world number four.
The split brings an end to a decade-long partnership that began when Fontang started coaching Auger-Aliassime at the age of 16.
"After nearly ten years of working together, it has recently been decided that Wimbledon would be my last tournament with Frederic by my side as my coach," Auger-Aliassime said in an Instagram post on Friday.
"Since I was 16 years old, he has guided my development and helped me experience incredible moments through this sport. He has also been by my side during the toughest moments of my career.
"In those difficult times, I always found in him the calm, composure, and wisdom I needed to overcome those challenges. Looking back today, I can say that beyond being an outstanding coach, he has been a true mentor throughout my journey into adulthood."
Wimbledon 2026
Wimbledon is taking place from June 29th to July 12th at the All England Club in south-west London. With 128 players in the draw, it is the third of the four Grand Slams of the tennis season and the only one played on grass.
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