Naomi Osaka (大坂 なおみ Japanese pronunciation: [o̞ːsäkä näo̞mʲi], Ōsaka Naomi, born October 16, 1997) is a professional tennis player who represents Japan. Osaka has been ranked No. 1 by the Women's Tennis Association (WTA), and is the first Asian player to hold the top ranking in singles.
As of April 2020, she has won five titles on the WTA Tour, including two titles at both the Grand Slam and Premier Mandatory levels. Osaka won her first two Grand Slam singles titles in back-to-back Grand Slam tournaments at the 2018 US Open and the 2019 Australian Open.
Born in Japan to a Haitian father and a Japanese mother, Osaka has lived and trained in the United States since she was three years old. She came to prominence at the age of sixteen when she defeated former US Open champion Samantha Stosur in her WTA Tour debut at the 2014 Stanford Classic.