US Open champion Naomi Osaka wore a different face mask for each of her matches at Flushing Meadows this year.
They each carried the name of a Black American and aimed to highlight racial injustice in the United States to a wider audience:
Round One: Breonna Taylor
Taylor, 26, was shot dead by police in her apartment in Louisville, Kentucky on March 13.
One police officer involved was fired by the city's police department in June. Two other officers have been placed on administrative reassignment. No criminal charges have been filed against any of the three.
Round Two: Elijah Mcclain
McClain, 23, died after a violent encounter with police officers in with Aurora, Colorado in August last year.
His family filed a lawsuit against the city and its police last month, alleging murder and routine use of excessive force against Black people.
Round Three: Ahmaud Arbery
Arbery, 25, was fatally shot after being pursued by armed white men as he jogged through a suburban neighbourhood in Georgia in February.
Three white men have been charged with the murder of Arbery in a case that spurred a national outcry after cellphone video of the shooting was leaked on the internet.
Round 4: Travyvon Martin
Martin was an unarmed Black teenager whose killing by civilian George Zimmerman in Florida in 2012 helped spark the 'Black Lives Matter' movement.
Quarter-finals: George Floyd
Floyd died in hospital on May 25 after Minneapolis police officer Derek Chauvin knelt on the 46-year-old's neck for nearly nine minutes during an arrest.
His death triggered mass protests against racial injustice and police brutality in the United States that have spread internationally.
Chauvin and three other Minneapolis police officers were fired a day after a video of the incident emerged. Chauvin was subsequently charged with second-degree murder and the other three officers with aiding and abetting.
Semi-finals: Philando Castile
Castile was a 32-year-old Black man shot and killed by Minnesota police during a traffic stop in a suburb of St. Paul, Minnesota in 2016, prompting protests.
His girlfriend livestreamed the aftermath of the incident on social media, garnering national attention for the case.
A jury acquitted an officer on charges of felony manslaughter and reckless discharge of a firearm.
Final: Tamir Rice
Rice was a 12-year-old African-American boy who was fatally shot by police officer Timothy Loehmann in Cleveland, Ohio in 2014 while he played in a playground with a toy gun that fired plastic pellets.
In April 2016, Cleveland officials agreed to pay $6 million to settle a federal civil rights lawsuit filed by Rice's family.
Loehmann was fired in 2017 after an internal investigation found he provided inaccurate information on his application to join the police.
Photographs: Getty Images
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