Dominic Thiem's bid for French Open glory came to an end after an epic five-setter against Diego Schwartzman as number two seed Rafael Nadal breezed past Jannik Sinner under the floodlights at Roland Garros.
Austrian Thiem, who won the US Open just 23 days ago, finally wilted in the deciding set in a match of extraordinary quality.
Schwartzman made it a double celebration for Argentina, following Nadia Podoroska's shock win over another third seed, Elina Svitolina, by reaching his first grand slam semi-final.
After more than five hours of gripping drama, 5ft 7in Schwartzman felt 10ft tall as he wrapped up a 7-6 (1) 5-7 6-7 (6) 7-6 (5) 6-2 victory.
Schwartzman said: "Dominic is one of the best players right now in the world.
"He won the last grand slam, he is a two-time finalist here, and I have a lot of respect for him.
"That's why this match is very important for me. I played a few five-setters here and I never won. I think at the end this night I deserved to win."
After two gruelling sets were shared the third, which featured eight breaks of serve, felt pivotal.
Schwartzman squandered a set point on the Thiem serve with a forehand which floated long, was promptly broken in the next, but then hit back to take it to a tie-break.
An outrageous drop shot from the baseline which flopped almost apologetically over the net brought up two set points for Thiem.
Battling Schwartzman saved both, but Thiem dispatched a third with an overhead to take the lead for the first time in the match.
Yet Schwartzman forged ahead in the fourth and had three set points on his own serve, only for Thiem to save the lot – including one with a scarcely believable forehand pass on the run – to take it to 5-5.
However, Schwartzman took the subsequent tie-break and, amidst a superhuman effort from both players, the 28-year-old from Buenos Aires had more left in the tank in the decider.
Thiem admitted: "To be honest, I was over the limit today. But if I had won, I mean, like Diego in that case, he has two days off now. Maybe I would have recovered.
"Even though I'm physically and mentally on the edge, you never know in a slam. Especially with tomorrow and Thursday off, two full days to recover. You never know what's happening.
"But at the end I gave everything I had out there. It was an amazing match. I think the first in my career over five hours. Diego fully deserves it."
In the late match on Court Philippe Chatrier, which finished at 12.25am on Wednesday morning, second seed Nadal eclipsed Jannik Sinner in three sets 7-6 (4) 6-4 6-1.
The 19-year-old Italian, reigning Next Gen ATP finals champion, had already beat two top-15 ranked players on his way to a first Grand Slam quarter-final.
Sinner, currently ranked 75 in the world, pushed Nadal in the opening set, breaking to lead 6-5 before the Spaniard – chasing a 13th Roland Garros crown and what would be a record-equalling 20 grand sNo wlam trophies – recovered to force the tie-break, which he took 7/4.
The Italian bounced back in the second to race out to a 3-1 lead, however Nadal relied on his veteran experience to clamber his way back and take the set before running away with it in the third.
The result sets up a mouth-watering semi-final matchup between Nadal and Schwartzman.
Earlier, in the men's doubles, British duo Jamie Murray and Neal Skupski missed out on a place in the semi-finals.
The 13th seeds were beaten 6-4 6-4 by German pair Andreas Mies and Kevin Krawietz, the defending champions.
