Teenager Bencic stuns Jankovic
Belinda Bencic became the youngest quarter-finalist at the US Open since her Swiss compatriot Martina Hingis won the title in 1997 with a 7-6 (8-6) 6-3 victory over ninth seed Jelena Jankovic.
The 17-year-old works with Hingis' mother and former coach Melanie Molitor and the two are very close.
It was Bencic's second victory over a top-10 player in a row after her third-round win against Angelique Kerber.
Speaking after that match, Hingis said of Bencic: "I think there is huge potential for her.
"I definitely think she can be top-five. She's on the way to get there. How far, it's up to her. Nobody can play the matches for her and win matches, win the tournaments.
"But she showed that she can win a big match when she has to. Hopefully there will be more opportunities in the near future. Maybe here."
Jankovic was the highest-ranked player left in the bottom half of the draw and that status now belongs to 10th seed Wozniacki.
In the last eight, Bencic will meet another unseeded player in China's Peng Shuai, who reached her first slam quarter-final by beating 14th seed Lucie Safarova 6-3 6-4.