"Defending US Open champion Naomi Osaka upset .. the 21-year-old’s quest to win back-to-back titles in New York came to an end Monday when she was ousted by giant killer Belinda Bencic, 7-5, 6-4."

http://www.kabc.com/news/defending-us-open-champion-naomi-osaka-upset-by-belinda-bencic/