Osaka's 1-6, 6-3, 6-3 victory on Saturday in New York adds to her trophies from the 2018 U.S. Open and 2019 Australian Open.
The 22-year-old was born in Japan and now is based in the United States.
Beyond Osaka's play, she silently points to social justice activism as she takes the court wearing her cloth face masks. Since her first match two weeks ago, Osaka has worn seven face masks to highlight seven people who have died in interactions with law enforcement or have faced racial injustice.
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The names on Osaka's masks were: Breonna Taylor, Trayvon Martin, George Floyd, Philando Castile, Elijah McClain, Ahmaud Arbery and Tamir Rice, whose mask she wore Saturday.
"I feel like I'm a vessel at this point, and in order to spread awareness," Osaka told ESPN, acknowledging the global reach of tennis.
"I'm aware that tennis is watched all over the world, and maybe there is someone that doesn't know Breonna Taylor's story," Naomi Osaka said after winning her first U.S. Open match this year, ABC News reports. "I have seven (masks), and it's quite sad that seven masks isn't enough for the amount of names," she said.
The final was played at a nearly empty and mostly silent Arthur Ashe Stadium, a facility with more than 23,000 seats.
Fans were banned from the U.S. Open this year because of the coronavirus pandemic, although some tournament workers did dot the stands Saturday.
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