Caroline Wozniacki thrilled the New York crowd with a stunning win over fifth seed Maria Sharapova at the US Open.
The Dane, seeded 10th, won 6-4 2-6 6-2 on a stiflingly hot afternoon at Flushing Meadows.
Wozniacki, 24, is through to her first Grand Slam quarter-final since 2012, and plays Italy’s Sara Errani next.
“It means so much to me – it’s been a bit up and down for me this year,” said Wozniacki.
“It’s a new year and I’ve gotten older, and hopefully a little wiser. I feel good. I feel comfortable when I play out there.
“The crowd was amazing today. It’s just so much fun to play out there again on the big court.”
Roared on by the majority of spectators on Arthur Ashe Stadium, the 2009 finalist looked back to her best as her superb defensive ability proved too much for Sharapova in a pulsating final set.
And she said that training to run the New York Marathon in November was aiding her game, adding: “I think it will help me a lot. Today was a tough battle out there. It was humid; it was hot; I had to change my dress.
“That rarely happens. It was just soaked. Definitely it’s helping, because I felt fresh out there and I felt like I could keep going.”
Wozniacki has slipped from the very top of the game after finishing as year-end world number one in 2010 and 2011, but in recent months there have been signs of a resurgence.