#NextGenATP Frenchman Arthur Fils advanced on his US Open debut Tuesday, clawing past 24th seed Tallon Griekspoor in a five-set thriller to reach the second round.

The 19-year-old battled hard throughout the three-hour, 58-minute match, striking 61 winners to advance 4-6, 6-3, 5-7, 6-4, 7-5. Fils will next face Italian Matteo Arnaldi, who competed at the Next Gen ATP Finals in 2022.

Fils has enjoyed a breakthrough season on the ATP Tour, winning his first title at this level on home soil in Lyon in May. The Frenchman is currently fourth in the Pepperstone ATP Live Race To Jeddah (953 points) and is aiming to make his debut at the Next Gen ATP Finals, to be held in Jeddah, Saudi Arabia for the first time.

[ATP APP]

The 19-year-old will be joined in the second round by fellow #NextGenATP star Alex Michelsen. The American wild card captured a 6-4, 6-3, 6-4 win against Spaniard Albert-Ramos Vinolas on his major debut.

Michelsen is seventh in the Live Race To Jeddah (492 points) after a standout few months on Tour. The 19-year-old advanced to his maiden tour-level final in Newport in July and reached the third round in Winston-Salem last week.

Aiming to compete at the 21-and-under event for the first time, Michelsen will look to earn more wins in New York to boost his chances. He will next play 23rd seed Nicolas Jarry after the Chilean defeated #NextGenATP Frenchman Luca Van Assche 6-3, 3-6, 6-2, 7-6(3).