Chrissie Evert won the biggest battle of her life in a hospital.

Now, Evert is sharing details of her fight with ovarian cancer in an interview with her friend, Mary Carillo, on HBO's Real Sports. Carillo's interview with Evert will air on Real Sports tonight, Tuesday, June 21st, at 10 p.m. Eastern time.

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"In tennis you can control the situation a lot better; in this type of thing you can't control it," Evert says of her cancer battle.

Evert shares "my sister's death saved my life" in her HBO interview with Mary Carillo.

The former world No. 1 completed her sixth and final chemotherapy session to treat stage 1 ovarian cancer last month. Evert shared the celebration day on social media.

"I'm a little out of it (meds) but nonetheless, thankful and relieved I finished my six chemo treatments," Evert posted on Twitter alongside a touching video of her thanking the medical team who cared for her during chemotherapy.