Sue Bird will go down as one of the greatest players in WNBA history. But right now, the 11-time All-Star is playing for more than championships and personal accolades. She’s playing to elevate her voice on the issues that matter.

In a new essay co-written with WNBA player Nneka Ogwumike and published on Phenomenal Media, a new platform that aims to bring awareness to social causes, Bird writes about why she feels an obligation to advocate for equality and justice. As women playing sports, they say they’re intrinsically radical.

“This explains why activism has always been part of our DNA: because, by simply existing in spaces that weren’t built for us, women athletes are doing something revolutionary,” they write.

The WNBA started its bubble season Saturday at the IMG Academy in Bradenton, Fla., and Bird left the court before the national anthem was played ahead of Seattle’s first game, along with the rest of her teammates. The New York Liberty did the same.

Every player was wearing a “Black Lives Matter” shirt with the phrase “Say her name” on the back, which is a reference to Breonna Taylor, who was killed by police in her own home in Louisville, Ky. None of the three officers involved have been arrested over the last 100 days, though one was fired from the department.

In a weekend full of plenty of performative activism from baseball players who knelt before the national anthem, it was a profound visual and statement.

Bird has been an outspoken advocate for social justice causes in recent years, most recently co-hosting the ESPYs with Russell Wilson and her girlfriend, Megan Rapinoe. Bird and Rapinoe talked about the complicity of white silence, with Bird examining her previous trepidation about speaking out.

“Do Black lives matter to you when they’re not throwing touchdowns, grabbing rebounds, serving aces?,” Bird asked. “If that was uncomfortable for you to hear, good. I used to shy away from moments like this, because it’s convenient to be quiet, to be thought of as safe and polite.”

In their essay on Phenomenal Media, Birdand Ogwumike talk about how this season is about far more than basketball.

“This moment is so much bigger than sports,” they write. “For WNBA players like us, it presents an opportunity to represent ourselves—on the world stage—as we’ve always been. By using our platform to shine a light on injustice, presenting a tangible example of strong allyship, and contributing to what’s become the largest social movement in American history, we aspire to instill change that ripples far beyond the WNBA.”