Alex de Minaur’s ATP Finals chase has been cut short in a brutal upset in Antwerp at the hands of France’s Hugo Gaston.

The 77th ranked Frenchman defeated the tournament’s No.1 seed 6-3, 3-6, 7-5.

Gaston converted three of four break points to claim a strong advantage over the Australian, who he has now beat twice having defeated de Minaur at the 2022 French Open.

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The Frenchman produced a remarkable shot in the opening set, smashing a de Minaur lob shot over his shoulder to leave the Australian star stunned.

The “wizardry” play prompted an applause from the crowd and his on court rival.

“One of the moments of the year let alone this tournament,” an ATP Tour commentator said.

Gaston, 24, required a medical timeout in the second-set for what seemingly appeared to be a groin injury, which was causing him to hobble, but returned soon after lifted his strategy to eliminate de Minaur.

“It was really close,” Gaston said post-match.

“Alex is such a great player, playing unbelievable tennis this year and in the past few years.”

The defeat was a costly for de Minaur as his chance to gain valuable points in bid of being one of the top eight men’s players to qualify for the final in the ATP Live Race to Turin.

Novak Djokovic’s defeat to Jannik Sinner at the Shanghai Masters saw de Minaur drop outside the required qualification, sitting in ninth.

De Minaur is locked in to compete at the Vienna Open next week before taking on the Paris Masters.

Gaston’s triumph marked the end of the European Open’s top three seeds campaigns, with Stefanos Tsitsipas and Felix Auger-Aliassime also falling short in the quarter finals.

The Frenchman will face Spain’s Roberto Bautistia Agut in the semi final, who downed third seed Auger-Aliassime 3-6, 6-2, 7-6 (8-6).