Blockx converts late Madrid call-up into breakthrough semi-final run

Alexander Blockx arrived at the Madrid Open expecting to play the qualifying rounds, but the Belgian has made the most of his late promotion to the main draw after a string of withdrawals, riding a wave of confidence to the semi-finals.

The 21-year-old toppled seeded players including Brandon Nakashima, Felix Auger-Aliassime and Francisco Cerundolo before ending the title defence of Casper Ruud with a 6-4 6-4 win on Thursday to set up a last-four meeting with Alexander Zverev.

Currently ranked 69th in the world after sitting outside the top 100 two months ago, Blockx can enter the top 30 with another upset, but the Belgian said the week had already gone beyond anything he imagined.

"I was already happy with getting into the main draw ... at the last minute on Friday, just before the deadline. Winning my first match (against Cristian Garin) was already a bonus," Blockx said. "Then all the other matches, I never thought I'd get that far. But once you get confident and you feel your game, a lot can happen."

Blockx has struggled for momentum on the ATP Tour following his run to the Next Gen ATP Finals title clash in December, but he showed his potential with a run to the third round of the Monte Carlo Masters last month.

His Madrid campaign and the win over two-time French Open finalist Ruud offered further validation for a player still building belief on clay.

"It's nice beating the defending champion, whose favourite conditions are here. That shows I can play well on clay too," Blockx added. "The ranking is going up really fast. It's nice to be able to play bigger tournaments now. I don't know the ceiling, I'll just see match by match, and hopefully get as high as I can."

Blockx meets Zverev later on Friday while world number one Jannik Sinner meets Arthur Fils in the other semi-final.