Naomi Osaka

Osaka returned to tennis in the middle of July. At the US Open in August, she reached the third round at a Grand Slam event for the third time this year. She upset No. 30 CoCo Vandeweghe in the first round before losing to No. 9 Madison Keys in three sets. During her match against Keys, she had a 5–1 lead in the third set before ultimately losing in a tiebreak. After the tournament, Osaka began the Asian hard court season with two tournaments in Tokyo, first losing in the second round at the Japan Women's Open. Having already reached her first two career WTA quarterfinals earlier in the year, she then made her breakthrough as a wild card at the Premier level Pan Pacific Open. She upset No. 12 Dominika Cibulková and No. 20 Svitolina on the road to making her first WTA final at the age of 18. At the time, Cibulkova was the highest ranked player she ever defeated. Additionally, she was the first Japanese player to contest the final at the event since Kimiko Date in 1995. Osaka ultimately finished runner-up to Caroline Wozniacki. Nonetheless, she entered the top 50 of the WTA rankings for the first time. At the end of the season, she was named the WTA Newcomer of the Year.

Naomi Osaka was born on October 16, 1997, in Chūō-ku, Osaka in Japan to Tamaki Osaka and Leonard François. Her mother is from Hokkaido, Japan, and her father is from Jacmel, Haiti. She has an older sister named Mari who is also a professional tennis player. The two girls were given their mother's maiden name in accordance with Japanese law that requires children with one foreign parent to take the last name of their Japanese parent in order to be included in their koseki, or family registry. Osaka's parents met when her father was visiting Hokkaido while he was a college student in New York.

When Osaka was three years old, her family moved from Japan to Valley Stream, New York on Long Island to live with her father's parents. Osaka's father was inspired to teach his daughters how to play tennis by watching the Williams sisters compete at the 1999 French Open. Having little experience as a tennis player himself, he sought to emulate how Richard Williams trained his daughters to become two of the best players in the world, despite having never played the sport. François remarked that, "The blueprint was already there. I just had to follow it," with regard to the detailed plan Richard had developed for his daughters. He began coaching Naomi and Mari once they settled in the United States. In 2006, Osaka's family moved to Florida when Naomi was eight or nine years old so that they would have better opportunities to train. Naomi practiced on the Pembroke Pines public courts. When she was 15 years old, she began working with Patrick Tauma at the ISP Academy. In 2014, she moved to the Harold Solomon Tennis Academy. She later trained at the ProWorld Tennis Academy.

Osaka never competed on the ITF Junior Circuit, the premier international junior tour, and only played in a small number of junior tournaments at any age level. She instead skipped to the ITF Women's Circuit and played her first qualifying match in October 2011 on her 14th birthday. She then made her professional main draw debut in doubles at her next tournament in March with her sister Mari. Meanwhile, she did not qualify for her first singles main draw until July in her seventh such attempt. Her best result of the 2012 season came at the ITF $10K event in Amelia Island, where she lost to her sister in the semifinals. Osaka has never won a title at the ITF level, only managing to finish runner-up on four occasions. Her first two finals came at the $25K level, one of which was in June 2013 in El Paso, Texas. The other was in March 2014 in Irapuato, Mexico and included a victory over her sister.

In September 2013, Osaka turned professional shortly before turning 16 years old. She entered her first two qualifying draws on the WTA Tour that same month at the Challenge Bell in Québec and the Pan Pacific Open in Tokyo. The latter event was her first opportunity to compete professionally in Japan. The following summer, Osaka qualified for her first WTA main draw at the 2014 Stanford Classic. In her tour level debut, she upset world No. 19 Samantha Stosur in a tight match where she saved a match point in the second set tiebreak and came back from a 5–3 deficit in the third set. She was still just 16 years old and ranked No. 406 at the time. Osaka also won a match as a wild card at the Japan Women's Open, her only other WTA main draw of the year. These victories helped her progress into the top 250 of the WTA rankings before the end of the season.

Osaka was coached by her father Leonard François from the age of three. Patrick Tauma was one of her first coaches after she began playing on the ITF Women's Circuit. He was her coach in 2013 when she reached her first ITF final. In 2014, she spent seven months training at an academy run by Harold Solomon, a former top five player and French Open finalist who has coached many top women's tennis players including Jennifer Capriati and Mary Joe Fernández. Under Solomon, Osaka defeated Sam Stosur for her first WTA match win. Following her loss at the 2016 US Open where she could not convert a 5–1 lead in the third set, the Japan Tennis Association helped arrange for David Taylor to be her new coach.

Despite not winning another WTA main draw singles match in 2015, Osaka continued to climb up the rankings. She reached her two highest level ITF finals, the first at the $75K Kangaroo Cup in Japan and the second at the $50K Surbiton Trophy in the United Kingdom. Following these runner-up results, Osaka was ranked high enough to enter qualifying at the last two Grand Slam singles events of the year, Wimbledon and the US Open. She won her first match at the US Open, but was unable to qualify for either main draw. Nonetheless, Osaka had a strong finish to the year. In October during the WTA Finals, she won the Rising Stars Invitational four-player exhibition tournament, defeating heavy favorite and world No. 35 Caroline Garcia in the final. Continuing to play in November, Osaka then reached the biggest final of her career at the WTA 125K Hua Hin Championships in Thailand. After a semifinal at a $75K event in Japan, she finished the year ranked No. 144.

Osaka entered the Australian Open as the fourth seed and also one of eleven players in contention for the world No. 1 ranking. She made it to the final against Petra Kvitová, having beaten Hsieh Su-wei in the third round despite being one set, 2–4 and 0–40 down at one point. Anastasija Sevastova also won the first set against her in the fourth round, while No. 8 Karolína Plíšková pushed her to three sets in the semifinals. After Osaka won the first set in the final, Kvitová saved three championship break points before breaking Osaka in back-to-back service games to win the second set. Nonetheless, Osaka recovered to win the championship. She was the first woman to win consecutive Grand Slam singles titles since Serena Williams in 2015, and was the first player to follow up her first Grand Slam singles title with another at the next such event since Jennifer Capriati in 2001. She also became the first Asian player to be ranked No. 1 in the world in singles. Despite this title, she parted ways with her coach Sascha Bajin following the tournament.

After her huge improvement the previous year, Osaka was unable to set a new career high ranking in 2017. Nonetheless, she maintained a steady ranking throughout the season, rising no higher than No. 44 while falling no lower than No. 68, her year-end ranking. She did not win more than two main draw matches at any event all year.

Following her lack of improvement in 2017, Osaka hired Sascha Bajin to be her coach in the offseason. In their second tournament together, Osaka produced her career best result at a Grand Slam event. At the Australian Open, she reached the fourth round after defeating two top-twenty players in Elena Vesnina and hometown favorite Ashleigh Barty, ultimately losing to world No. 1 Simona Halep. This result helped her return to the top 50 within the next month.

Osaka made her Fed Cup debut for Japan in 2017, while the team was competing in the Asia/Oceania Zone Group I. Japan won all nine of their rubbers to advance out of their round robin pool. Although Osaka won her singles match in the play-off against Kazakhstan, the team lost their other two matches and was not able to advance. The following year with Osaka absent, Japan was able to defeat Kazakhstan in the same group to advance to the 2018 World Group II Play-offs. In this stage, they hosted Great Britain in a usual five rubber tie. At this point, Osaka returned to the team and won her opening match against Heather Watson. After she lost her next rubber to Johanna Konta, Kurumi Nara was also able to defeat Watson to set up a decisive doubles match. Japan won that final rubber to earn promotion to World Group II in 2019.

After her success in the early months of the season, Osaka had a relatively quiet middle of the year. She reached the third round at both the French Open and Wimbledon, matching her best performance at each tournament. The closest she came to winning another tournament was on grass at the Nottingham Open, where she lost to top seed Barty in the semifinals. Osaka did not have another breakthrough result until the US Open, where she won her second title of the year. Like at Indian Wells, she only dropped one set in the middle round of the event, this time to No. 20 Aryna Sabalenka. In the three early rounds, she only lost a total of seven games and notably recorded a double bagel victory against Aliaksandra Sasnovich. Osaka was drawn against Madison Keys in the semifinals, and was able to avenge her tough loss from the 2016 US Open to advance to the final. In the final, she defeated Serena Williams for the second time in 2018 to win her first grand slam title. The match was marred by an on-court dispute between Williams and the umpire highlighted by Williams receiving a game penalty and boos from the crowd both during the match and the award ceremony. Osaka later said that the win was "a little bit bittersweet" and "it wasn't necessarily the happiest memory." Nonetheless, she became the first Japanese woman to contest a Grand Slam singles final and the first Japanese Grand Slam singles champion.

Osaka made her Hopman Cup debut in 2018 with Yūichi Sugita. Japan was making their first appearance at the exhibition tournament since 2001. They were grouped with Switzerland, the United States, and Russia, and lost all three of their ties. Osaka's only match win came in singles against Russian Anastasia Pavlyuchenkova. She also had a big highlight in the mixed doubles match against Switzerland when she served an ace past Roger Federer.

Osaka credited improving her mental approach and cutting down on unforced errors for her breakthrough season in 2018. At the Wuhan Open towards the end of the year, she noted, "I think my biggest improvement is mental. My game is more consistent, there are not so many unforced errors. I'm not sure how many I hit today, but sometimes last year I was hitting a lot!" She attributed some of these changes to her coach Sascha Bajin, saying, "Since I was working with [Bajin] — and I tend to be a bit negative on myself — I feel like I've gotten a little bit more optimistic ... I fight myself a lot, so he's sort of been, like, the peacemaker." Bajin also agreed with Osaka on the impact of having a patient, positive approach in each match.

After a lackluster 2017 season, she switched coaches to Sascha Bajin, who had previously served as a hitting partner to top players such as Serena Williams, Victoria Azarenka, and Caroline Wozniacki. With Bajin as her coach, Osaka won her first Premier Mandatory title and two Grand Slam singles titles. She also rose to No. 1 in the world after having never previously been ranked above No. 40. Bajin was named the inaugural WTA Coach of the Year in 2018. Shortly after her 2019 Australian Open title, Osaka surprisingly split with Bajin, saying, she "wouldn't put success over [her] happiness." She hired Jermaine Jenkins to be her new coach the following month. Jenkins had previously worked as a hitting partner for Venus Williams. Osaka temporarily replaced him with her father in September. She won her first two tournaments with him back as her coach. She then hired Wim Fissette for the start of the 2020 season.

Osaka is one of the most marketable athletes in the world. She earned an estimated $16 million in endorsements alone in 2019, which placed her second among all female athletes behind only Serena Williams who earned $25 million. The following year, she became the highest-paid female athlete of all time, having earned $37.4 million in total, including $34 million in endorsements. Overall, she was the 29th highest-paid athlete in 2020 and the 8th highest-paid athlete in endorsements alone.

Osaka has a multi-ethnic background, with her father being born in Haiti and her mother being from Japan. She has said, "My dad's Haitian, so I grew up in a Haitian household in New York. I lived with my grandma. And my mom's Japanese and I grew up with the Japanese culture too, and if you're saying American, I guess because I lived in America, I also have that too." Her Haitian grandparents only spoke to her in Creole because they did not know English, while her mother conversed with her in Japanese. Osaka decided to relinquish her US citizenship in 2019 so that she could represent Japan at the 2020 Tokyo Olympics and also in accordance with Japan's Nationality Act, which requires dual citizens to choose a nationality by the age of 22. Osaka can understand Japanese, but is not very confident speaking the language. She has said, "I can understand way more Japanese than I can speak." At press conferences, Osaka can take questions in Japanese but typically will answer them in English.

Osaka began taking part in activism in 2020. She joined in Black Lives Matter protests over the summer of 2020, including attending protests in Minnesota following George Floyd's death; penning an op-ed in Esquire magazine; indicating she was going to sit out her semi-final match at the Western & Southern Open; and wearing masks with the names of those who had died in police shootings.