Martina Navratilova stunned the tennis world on Sunday, announcing that that she has been diagnosed with Stage 1 throat cancer and early-stage breast cancer.

The 66-year-old American-Czech citizen is one of the greatest tennis players of all time, and the best in the history of the Wimbledon tennis championships; she's won the tournament a record nine times, and reached the final on 12 occasions.

Navratilova initially discovered an enlarged lymph node in her neck in early November. After getting testing done, a suspicious form was then additionally found in her breast. This comes 13 years after she was given the all-clear from breast cancer following radiation treatment, according to Stuart Fraser of The Times.

“This double whammy is serious but still fixable, and I’m hoping for a favorable outcome,” Navratilova said. “It’s going to stink for a while, but I’ll fight with all have I got.”

Navratilova will begin treatment this month, with a strong prognosis considering a history of positive outcomes for these cancers, per tennis.com. The throat cancer is type HPV, which typically responds well to treatment. Six months after her breast cancer diagnosis in 2010, Navratilova was deemed cancer-free following a lumpectomy and six weeks of radiation.

“I really didn't talk much about breast cancer before I had it,” she previously told People magazine. “Now, I'm approached by women and we share our stories. It's encouraging to see that there's life after cancer.”

Navratilova is a 59-time Grand Slam champion across singles, doubles, and mixed events, which is the most in the Open Era. She was a top competitor in all facets of the sport from the mid-1970s until the mid-2000s, retaining the title of World No. 1 in singles for an incredible 332 weeks, and 237 weeks in doubles, making her the only player in history to have held the top spot in both disciplines for over 200 weeks.

Prayers up for Martina Navratilova as she faces this latest obstacle in her incredible career.