2 games in each set. He lost in a five set battle to the 24th seed Matteo Berrettini. Monfils finished the year in the top 10 at World No. 10 since February 2017. 2020: Ninth & Tenth titles, loss of form during COVID season At the 2020 Australian Open, Monfils lost in the fourth round to Dominic Thiem. Monfils won the ninth ATP Tour singles title of his career at the Open Sud de France, defeating Vasek Pospisil in straight sets 7–5, 6–3. Monfils won his second title of the year at the Rotterdam Open, successfully defending his title by defeating Félix Auger-Aliassime in the final. This marked the first time Monfils has won two ATP Tour titles in a season. At the French Open, Monfils lost in the first round to Alexander Bublik. 2021: Continued struggles, Olympics, 500 ATP career wins Monfils lost in the first round of the 2021 Australian Open to Emil Ruusuvuori in five sets. He picked up his first win in over a year in Lyon, beating lucky loser Thiago Seyboth Wild in straight sets. In Belgrade's second tournament, Monfils lost to qualifier Roberto Carballés Baena in a third set tie-break. At the French Open, Monfils defeated Albert Ramos-Viñolas in 4 sets, after saving a set point in the second set tie-break. In the second round he lost to Mikael Ymer. Following the clay season, Monfils quickly turned to the grass. At the 2021 Halle Open, Monfils continued to struggle as he lost in the opening round to Lloyd Harris. Following this, Monfils quickly turned to the next event of the 2021 Eastbourne International. He lost in the opening round again, this time to qualifier Max Purcell. At the 2021 Canada Masters 1000, Monfils made his first quarterfinal appearance of the year after defeating John Millman and Frances Tiafoe. He lost to John Isner in straight sets. In the next Masters at the 2021 Western & Southern Open in Cincinnati, he defeated Alex De Minaur to reach the last 16, and the 500th win in his career on the ATP tour marking an important milestone. Monfils became the 11th active player to reach 500 singles match wins. Monfils made his first semifinal of the year at the 2021 Moselle Open. As the 3rd seed, he defeated lucky loser Philipp Kohlschreiber in the second round to reach his second tour-level quarterfinal of the season and 8th