Alexander Blockx is living the dream in Madrid. The 21-year-old Belgian sensation continued his stunning run at the Madrid Open on Thursday, knocking out defending champion Casper Ruud 6-4, 6-4 in the quarterfinals.

Ranked 69th in the world, Blockx had never won an ATP Tour match on clay before his third-round breakthrough in Monte Carlo just three weeks ago. Now, he's dispatched the tournament's top seed and reigning champion on the biggest stage of his young career.

Blockx's composure was remarkable from the start. He broke Ruud early in the first set and held firm against the Norwegian's trademark heavy topspin forehands. The second set followed a similar script, with Blockx mixing powerful groundstrokes with clever drop shots to keep Ruud off balance.

For Ruud, the loss ends his title defense in Madrid and marks another surprise early exit at a tournament he dominated in 2025. The 27-year-old had been seeking his third Masters 1000 title.

Blockx's run is the kind of Cinderella story tennis fans love to see. He'll now face an even stiffer test in the semifinals, but after this performance, no one will underestimate him. His journey from clay-court novice to Madrid semifinalist in under a month is rewriting expectations for this rising Belgian star.