French Open champion and third seed Garbine Muguruza was sent spinning out of the US Open second round on Wednesday by Latvia's Anastasija Sevastova.
The 48th-ranked Sevastova survived some late nerves to close out the world number three from Spain 7-5, 6-4 and set up a third-round clash with Ukrainian Kateryna Bondarenko, a 5-7, 7-6 (7/5), 7-5 winner over China's Zheng Saisai.
"I was shaking a little bit at the end," admitted 26-year-old Sevastova, who stepped away from the game in 2013, tired of dealing with injuries.
She returned in 2015, and reached WTA finals in Mallorca and Bucharest this year.
Her victory cost Muguruza her slim chance of overtaking Serena Williams atop the world rankings, and the magnitude of her biggest win on one of the game's biggest stages wasn't lost on Sevastova.
"On Ashe (court), a night match, what's going to be bigger," she said. © AFP, 2016