Emma Navarro is one of four first-time quarter-finalists at Wimbledon after knocking out world number two Coco Gauff.
The 23-year-old from New York, seeded 19, stunned the reigning US Open champion 6-4 6-3 on Centre Court.
It means Wimbledon remains the only grand slam at which Gauff has failed to make the quarter-finals.
Navarro will face French Open runner-up Jasmine Paolini in the last eight.
“She’s a great player, she’s not an easy out and always puts up a great fight to the end, so I think it’s going to be a great match and I’m really excited,” said Navarro.
American 12th seed Madison Keys left Court One in tears after serving for the match against Paolini before being forced to retire injured.
Keys was 5-2 up in the deciding set of an entertaining match when she suffered a hamstring injury.
She received treatment and went off the court, returning heavily strapped up, but eventually called it a day at 5-5.
Paolini, the seventh seed from Italy, said: “I’m very sorry for her. It’s sad after a really good match. Really tough, lots of up and downs. I feel a bit happy but also sad for her because it’s not easy to win like that.”
The second quarter-final will see Croatian Donna Vekic take on Lulu Sun, the qualifier from New Zealand.
An emotional Vekic reached the last eight at the 10th time of asking after beating Spain’s Paula Badosa 6-2 1-6 6-4 in a long, rain interrupted match on Court Two.
She said: “It’s been such a long day. The stress has been building up since I warmed up. So it was just also a big relief to finally get it done.
“To win and make quarters at Wimbledon, I feel like I’m living my dream. So I’m just really happy.”
Sun beat the last British player standing, Emma Raducanu, to become the first qualifier to reach the last eight since Kaia Kanepi in 2010.
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