Before and after her first-round victory at the U.S. Open, Naomi Osaka wore a mask bearing the name of Breonna Taylor, a Black woman who was fatally shot by police. It's just one of seven face coverings, each in honor of a different person, that Osaka brought to Flushing Meadows - the same number of wins it takes to claim a Grand Slam trophy. The world's highest-earning female athlete hopes she can get the chance to raise awareness about racial injustice by using each mask during her stay in New York. "It's quite sad that seven masks isn't enough for the amount of names, so hopefully I'll get to the finals so you can see all of them," said Osaka, the champion at the 2018 U.S. Open and 2019 Australian Open. The No. 4-seeded Osaka's movement was an issue at times; she is coming off a left hamstring injury that forced her to withdraw from the final of the Western & Southern Open on Saturday. It was during that tournament last week that Osaka took a public stand by saying she would refuse to play her semifinal, joining athletes in various other sports who walked out to protest the shooting of Jacob Blake, a Black man, by a police officer in Wisconsin. Osaka's move prompted tournament organisers to halt action entirely for a day.