Just 14 hours after Stan Wawrinka upset top seed Novak Djokovic, another Swiss player has beaten another No. 1 seed.
Defending U.S. Open champion Naomi Osaka suffered an upset straight-set loss (7-5, 6-4) to No. 13 Belinda Bencic in the fourth round on Monday, ending the world No. 1's hopes of winning her second-straight title in New York and third Grand Slam in the last 12 months.
Bencic, 22, jumped to an early 2-0 lead in the first set, generating four break points in the third game before Osaka fought back to win three straight games to take a 3-2 lead.