NEW YORK (Reuters) – American teenage tennis prodigy Coco Gauff appeared at a protest in her hometown of Delray Beach, Florida, on Wednesday, calling for racial and social justice after the death of George Floyd, an unarmed black man killed in police custody in the U.S.

“I was eight years old when Trayvon Martin was killed. So why am I here at 16 still demanding change?” said Gauff, days after posting a video on social media in which she pledged to use her voice to fight against racism.

Martin was an unarmed black teenager whose killing by civilian George Zimmerman 200 miles away in Sanford, Florida, in 2012 helped spark the “Black Lives Matter” movement.

“It breaks my heart because I’m fighting for the future for my brothers,” said Gauff. “I’m fighting for the future for my future kids, I’m fighting for the future for my future grandchildren.”

Floyd’s death on May 25 has sparked a week of sometimes violent protests and civil unrest in cities across the U.S.

Derek Chauvin, a white Minneapolis police officer who appeared in a cell phone video kneeling on Floyd’s neck, has been charged with murder.

Gauff, who rocketed to fame after a stunning upset victory over her idol Venus Williams at last year’s Wimbledon, spoke at the rally after her grandmother Yvonne Odom, who was the first black student at her high school here in 1961, addressed the crowd.

“It’s sad that I’m here protesting the same thing that she did 50-plus years ago,” said Gauff.