British number one Dan Evans came from a set down to beat Belgium's David Goffin and reach the semi-finals of the Monte Carlo Masters.
Evans, who claimed the biggest win of his career by beating Novak Djokovic in the previous round, won 5-7 6-3 6-4.
He fended off four break points at 4-4 in the final set to hold serve and then took match point at his first attempt to win in two hours and 46 minutes.
Evans will face Stefanos Tsitsipas in his first Masters Series semi-final.
The Greek world number five had taken the opening set 7-5 against Alejandro Davidovich Fokina when the Spaniard retired.
Evans will also team up with Neal Skupski for a doubles semi-final on Saturday after the pair beat Raven Klaasen and Ben McLachlan 1-6 7-6 (7-5) 10-4 in a deciding set tie-break.
"It's been a good week. I'm enjoying it," said Evans.
"It's easy to say everybody told me I'd be able to play on clay before. It's not that simple, is it? Otherwise we'd all be winning matches all the time. It's one of those things.
"I feel a bit more comfortable moving. It's been a lot easier. Obviously I have worked with a fitness trainer for a few weeks. We did a lot of footwork stuff, sliding. It's definitely helped."
However, Rafael Nadal failed to reach the last four for only the second time in his last 16 appearances, following a surprise defeat by Andrey Rublev.
The Spaniard was bidding for his 12th title in Monte Carlo but slipped to a 6-2 4-6 6-2 loss against sixth seed Rublev, who will now face Norway's Casper Ruud.
"I'm always sad to lose here, of course, because it's an important one for me. I missed an opportunity to start the clay-court season in the right way," said Nadal.
"But that's it. I can't complain. The only thing that I can do is go to Barcelona and keep practising, try to fix the things that didn't work well."
'A story no-one expected to be writing' - analysis
Russell Fuller, BBC tennis correspondent
For a surface on which British players are supposed to struggle, some remarkable clay court seasons have been compiled in recent years.
In 2015, Andy Murray won his first clay tournaments in consecutive weeks in Munich and Madrid, and four years later - with little previous hint of what was to come - Johanna Konta put together a thrilling run which culminated in a French Open semi-final.
And now Dan Evans, with just four tour level wins on clay before this week, has doubled his tally on the surface.
He saved 15 of the 17 break points he faced against David Goffin, with some clutch serving when most required in the decider.
Confidence, a smart game plan, and some exceptional execution have contributed to a story no-one expected to be writing.
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