Gabriel Diallo

Gabriel Diallo took the route Canadian tennis usually skips. Born in Montreal to a Guinean father and a Ukrainian mother who played handball, he speaks French, English and Russian and is learning Spanish — and rather than ride the junior fast track, he attended the University of Kentucky, becoming an All-American before turning pro at the end of 2022. Notably, Felix Auger-Aliassime's father, Sam Aliassime, is a former coach of Diallo's. His maiden Challenger title came at home in Granby in 2022, as a 519th-ranked wildcard.

At 6-foot-8, Diallo is built around a serve that plays exactly like the frame suggests. The first delivery is the platform — career numbers around 74% of points won behind it — and grass is where it all clicks. The ATP files him as a right-hander, and his return game lags the serve, which keeps the hard-court ledger near break-even while the lawns flatter him.

The breakout came at the 2024 US Open, where he qualified and upset 24th seed Arthur Fils to reach the third round before Tommy Paul stopped him. The 2025 clay swing built on it: as a lucky loser in Madrid he saved three match points to defeat No. 16 Dimitrov for the biggest win of his career and advance to his first Masters 1000 quarterfinal. Then came the grass. At the Libéma Open he beat Karen Khachanov and Ugo Humbert en route to the final, where he beat Belgium's Zizou Bergs 7-5, 7-6(8), becoming the first Canadian in the 21st century to claim a tour-level title on grass.

That title lifted him to a career-high ATP singles ranking of No. 33, achieved on 18 August 2025. Sitting at No. 54 now, behind Auger-Aliassime and Denis Shapovalov in the Canadian pecking order, Diallo is the next-wave server still hunting his first deep hard-court run to match the grass.