Entertainment Sports Naomi Osaka's Sister Mari Narrates Message of Their Deep Sibling Love: 'We Dreamed of Being Champions' PEOPLE exclusively shares "Voices of a Champion," a featurette narrated by Mari Osaka which tells her close sibling bond with younger sister Naomi Osaka By Karen Mizoguchi Published on July 20, 2021 09:00 AM Share Tweet Pin Email Naomi Osaka's supportive sister is opening up about their close bond. PEOPLE exclusively shares "Voices of a Champion," a featurette narrated by Mari Osaka which tells her close sibling bond with her younger sister Naomi, 23, who recently released her self-titled Netflix documentary last Friday. "We dreamed of being champions. Defying labels, courting excellence, each choosing victory over the other. Our parents organized our dreams and trained us to fulfill them. Their excellence reflecting in our character, in our discipline," says Mari, 25, as throwback footage and home videos of the sisters from their childhood. "Play became serious and we learned as I schooled you. Me: accustomed to winning; you: saying you'd beat me tomorrow," Mari shares in the voiceover with snippets of her playing against Naomi on the tennis court years ago. "The day you caught up to me something clicked in you, and that piece of your destiny became real. Each win builds a platform that we'll use to make impact, finding purpose on and off the court and opening ourselves up and cheering each other on," Mari adds as the clip shows a focused Naomi training before dominating in the U.S. Open tournaments. "Parallel paths. Becoming the champions we need. We dreamed of being champions, Mari and Naomi," the oldest Osaka sister concludes. Naomi Osaka Grieves Kobe Bryant's Death in Netflix Doc, Wonders How 'to Carry on His Mentality in Tennis' And in her new three-part Netflix documentary series, the Olympian, who will compete for Japan, speaks about her relationship with Mari. "My sister I hadn't seen her in a few months. I miss her a lot because we grew up together. We would work together every day until we were 17," says Naomi, who documented her international travels for tournaments amid a whirlwind career after defeating Serena Williams in the 2018 U.S. Open. "[Mari] helps me a lot, with the fashion stuff. I'm just the vessel for whatever she wants to do. To the people who know both of us, I'm the mean sister, right? I think I'm blunt but not on purpose. It also comes with being homeschooled and not having interactions with other people except my sister," Naomi shares. Want to get the biggest stories from PEOPLE every weekday? Subscribe to our new podcast, PEOPLE Every Day, to get the essential celebrity, entertainment and human interest news stories Monday through Friday. Mari's love letter to Naomi comes three months after she announced her retirement from professional tennis in March. "I am retired from playing tennis. It was a journey which I didn't enjoy ultimately but I'm grateful for all the memories and support I've gained and received over the years from the sport. I'm moving on now so you can look forward to new fun projects upcoming in the future," Mari wrote in a since-deleted Instagram post. The Osaka siblings previously competed against one another in March 2019 at the Miami Open. That same month, the currently No. 2 ranked female tennis athlete told The New York Times about growing up playing against Mari. "Up until I was 15 she was 6-0-ing me, ridiculous. I don't know what happened, maybe finally something clicked in my head, but for sure she was beating me," Naomi said. "In the win-loss record, she's up by like a million or something." Naomi Osaka is streaming on Netflix now.