Tsitsipas, the world’s fourth-largest player, was among the key players likely to upset the men’s tennis king, Novak Djokovic, in his quest for Olympic gold. The Greek-Serbian pushed to the limit in the last final at Roland Garros, losing in five rounds.

Against the French, ranked 28th in the world, he started the match well, taking advantage of two of his three breakout opportunities to break Humbert to seize the first leg.

Fought fiercely, the second commitment went to the Frenchman, who finally won the tiebreak. After injuring his right leg at the end of the round, Tsitsipas took a medical break before starting the third act.

Stefanos Tsitsipas needed medical leave after injuring his right leg late in the second set.

Photo: Getty Images / Clive Brunskill

To an apparent annoyance, the Greek broke twice in the third set, leaving Humbert to claim victory. The Frenchman has a date with Russia’s Karen Khachanov in the quarter-finals.

Accompanied by compatriot Maria Sakkari, Tsitsipas should face off a little later in the night the Canadian tandem formed by Felix-Auger-Aliassime and Gabriela Dabrowski in the mixed doubles.

Russian Olympic Committee representative Daniil Medvedev defeated Italian Fabio Fognini in three sets 6-2, 3-6, 6-2. He will face the second world number one, Pablo Carreno Busta, in the quarter-finals.

Japan’s Kei Nishikori also qualified for the next stage by defeating Belarusian Ilya Ivashka 7-6 (9/7), 6-0. He will face the winner of the duel between Djokovic and Spaniard Alejandro Davidovich Fokina.