Wozniacki said doctors diagnosed her with rheumatoid arthritis before the U.S. Open.
Reigning Australian Open champion Caroline Wozniacki was diagnosed with rheumatoid arthritis before the US Open, she revealed on Thursday.
At a press conference following her WTA Finals exit, which she suffered with a 5–7, 7–5, 6–3 loss to No. 7 Elina Svitolina in the final round of group play, Wozniacki told reporters she was diagnosed in August after talking to doctors after Montreal. Wozniacki began feeling fatigue after Wimledon and was unable to lift her arms over her head waking up one morning over the summer.
Rheumatoid arthritis is an autoimmune disease that causes fatigue and swelling of the joints.
Wozniacki still played in the U.S. Open as the No. 2 seed but lost in the second round to unseeded Lesia Tsurenko.
"In the beginning, it was a shock, just you feel like you're the fittest athlete out there, or that's in my head, that's what I'm known for, and all of a sudden you have this to work with," Wozniacki said. "It is what it is, and you just have to be positive and work with it, and there are ways that you can feel better so that's great."
Wozniacki said that she kept quiet about the diagnosis to avoid giving opponents a reason to believe she was not feeling well. She has been receiving treatment to manage the disease and believes it will not impact her career.
The 28-year-old Dane won her third title of the season at the China Open on Oct. 7 and qualified for the season-ending WTA Finals despite her earlier diagnosis.
"Winning in Beijing was huge," Wozniacki said. "It also gave me the belief that nothing is going to set me back. I'm going to work with this and this is how it is, and I can do anything. I know there are a lot of people in the world who are fighting with this and, hopefully, I can be someone they look up to and say if I can do this, then they can, too."