Norrie had only previously beaten one opponent ranked inside the world's top 10, a victory against American John Isner in 2018 which also came in Lyon
British number two Cameron Norrie earned the biggest win of his career by beating Austrian world number four Dominic Thiem in the Lyon Open.
Norrie had never beaten an opponent ranked in the world's top five but won 6-3 6-2 against US Open champion Thiem.
The left-hander has enjoyed a strong start to 2021, having already won a joint career-best tally of 21 matches.
The 25-year-old will play France's Arthur Rinderknech, who beat Italian Jannik Sinner, in the last eight.
Norrie, ranked 49th, played impressively throughout against a below-par Thiem, converting three of his four break points while not facing one himself.
"I'm so pleased to win, it's my highest-ranked win. I couldn't be happier," said Norrie, who has won 12 of his 15 clay-court matches this year.
"I'm moving well and playing a lot of matches so feeling good on my feet, hitting my forehand well and serving well.
"I'm looking forward to getting another match on the clay before Roland Garros."
While Norrie will go into this month's French Open with plenty of confidence – no matter how the rest of the week in Lyon pans out – it was a worrying defeat for top seed Thiem.
The 27-year-old is one of the world's leading players on the red dirt, having won 10 of his 17 titles on the surface, as well as finishing runner-up at Roland Garros in 2018 and 2019.
But he is still trying to rediscover his best form after taking two months away from the tour earlier this year.
Thiem said he needed a "small reset" after the physical and emotional nature of winning his maiden Grand Slam title at the US Open in September took its toll.
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