Dominic Thiem produced a stunning display to end Rafael Nadal's remarkable 21-match run on clay and reach the Madrid Open semi-finals.
Nadal had not lost a set or match on the red dirt since falling to Thiem at last year's Italian Open, but the Austrian proved to be his downfall once more with a 7-5 6-3 victory.
As a result, not only does Nadal's record-breaking streak of 50 sets won on a single surface come to an end, but the Spaniard will lose his world No 1 ranking to Roger Federer on Monday.
Meanwhile, Thiem - who lost the Madrid final to Nadal last year - will face South African Kevin Anderson in the semi-finals on Saturday.
Thiem is viewed as Nadal's closest challenger for French Open glory, which gets underway later this month, and the world No 7 was more than a match for the 16-time Grand Slam champion.
After squandering set point at 5-4 in the opening set, and allowing Nadal to level up at 5-5, Thiem broke again before closing out the set on serve to end the Spaniard's record-breaking streak.
Thiem was producing the same scintillating level of tennis which saw him overcome Nadal in Rome 12 months ago, and he moved a break up in the second set after an epic third game.
Nadal did break back in the sixth, but dropped serve immediately to hand the advantage back to Thiem, who held his nerve to close out the match.
"It really was bizarre," said Sky Sports pundit Annabel Croft. "I don't think anybody could have predicted that type of performance from Nadal.
"But Thiem completely raised his level. You compare that to Monte Carlo (where Nadal beat Thiem 6-0 6-2) - he was a world away from Nadal then. It's almost as if the shackles came off here, he was playing with freedom and absolutely went for broke. It was one of those golden matches."
Earlier in the day, sixth seed Kevin Anderson withstood a stern test from Serbian qualifier Dusan Lajovic to reach his first Masters 1000 semi-final.
Anderson, who had lost his previous 10 Masters 1000 quarter-finals, won 7-6 (7-3) 3-6 6-3 after more than two hours on court with the world No 95.
The Masters 1000 Series continues this weekend with our coverage of the ATP Madrid Open semi-finals on Sky Sports Arena starting from 3pm on Saturday.
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