Alexander Blockx has secured the most significant victory of his fledgling career. The Belgian, ranked 69th in the world, defeated Felix Auger-Aliassime, the third seed and world number five, 7-6, 6-3 to reach the last sixteen of the Mutua Madrid Open and record his first win over a Top 10 player.

The result reaffirms the player’s rapid progression in recent months. Blockx broke into the top 100 in March, achieved his highest ranking in April, and made a splash in Monte Carlo, where he defeated Flavio Cobolli, the world number 16, on his 21st birthday. In Madrid, he’s gone one step further by defeating a player in the top five.

The victory also carries historical significance. Blockx could now become the first Belgian to reach the quarter-finals in the history of the Mutua Madrid Open. Until now, names such as Olivier Rochus, Kristof Vliegen, Xavier Malisse and David Goffin had made it to the last sixteen, but none managed to surpass that threshold at the Caja Magica.

To achieve the feat, Blockx will have to get past Francisco Cerúndolo, who recently defeated Luciano Darderi. The Argentinian, a clay specialist and semi-finalist in 2025, will be the next test for a player who arrived in Madrid as one of the rising stars of the new generation and is hungry for more.

Junior Australian Open champion in 2023, a former world number one in his age group, and finalist at the Next Gen ATP Finals in 2025, Blockx is now transferring his credentials to the professional circuit. In Madrid, he has already delivered his first major blow and now has a unique opportunity for Belgian tennis.