Thiem, the last player to beat Nadal on the surface when he overcame the 16-time Grand Slam champion in May of last year, recorded a 7-5, 6-3 victory at the Caja Mágica.

The defeat for defending champion Nadal also ended his record run of 50 consecutive sets and means he will be replaced as world number one by Switzerland's Roger Federer when the rankings are published.

The Spaniard broke the previous mark of 49, set by American John McEnroe on carpet, when he overcame Argentina's Diego Schwartzman yesterday.

Thiem was also last player to take a set off Nadal on the surface when he beat the 31-year-old, a 10-time French Open winner, at the Italian Open in May 2017.

The Austrian, seeded fifth for the Madrid Open and considered one of the best clay-court players on the tour, will face sixth seed Kevin Anderson of South Africa in the last four.

Anderson battled past Serbian Dušan Lajović with a 7-6, 3-6, 6-3 win to progress to the semi-finals.

Dutch player Kiki Bertens was the first to book a place in the last four of the women's draw as she comfortably dispatched seventh seed Caroline Garcia of France in straight sets.

Bertens produced a superb performance to claim a 6-2, 6-2 victory.

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