Martina Navratilova, the retired tennis great who won 18 Grand Slam singles titles during her illustrious career, announced Monday that recent tests have shown she is cancer-free.

The 66-year-old woman said she had a full day of testing at Sloan Kettering Cancer Center and the results came back clean.

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Former Czech tennis player Martina Navratilova receives the golden racket during the Italian international tennis matches at the Foro Italico in Rome on May 21, 2023. (Massimo Insabato/Archivio Massimo Insabato/Mondadori Portfolio via Getty Images)

«Thank you to all the doctors, nurses, proton and radiation wizards etc. What a relief,» he wrote on Twitter.

Navratilova announced in January that she had been diagnosed with throat and breast cancer and would start treatment in a month. She had been diagnosed with a non-invasive form of breast cancer in 2010 and she underwent a lumpectomy.

«This double whammy is serious but it can still be fixed,» he told The Times earlier this year. «I’m hoping for a favorable outcome. It’s going to suck for a while, but I’ll fight with everything I’ve got.»

Martina Navratilova in Rome

Former Czech tennis player Martina Navratilova receives flowers during the international Italian tennis matches at the Foro Italico in Rome on May 21, 2023. (Massimo Insabato/Archivio Massimo Insabato/Mondadori Portfolio via Getty Images)

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She noticed an enlarged lymph node in her neck in November and a biopsy revealed early-stage throat cancer. She felt well enough to return to her television work with the Tennis Channel before the Miami Open in March.

Navratilova is considered one of the greatest tennis players of all time, topping the Mount Rushmore list with Serena Williams, Chris Evert, Billie Jean King and Margaret Court. She was ranked No. 1 in the world for 332 weeks and won 59 major titles in singles, doubles and mixed doubles competition.

Martina Navratilova protects her face

Martina Navratilova in London in 2004. (Bongarts/Bongarts/Getty Images)

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Notably, he won nine Wimbledon titles.

Associated Press contributed to this report.