American Danielle Collins said she has begun treatment for rheumatoid arthritis, an immune disorder that can cause debilitating swelling and pain in the joints.
The Florida native enjoyed a breakout season in 2019, reaching a career-high ranking of 23rd in the world and reaching the Australian Open semi-finals in January.
“I have not been feeling all that great for quite some time, but it has been somewhat of a relief and completely validating to understand the cause behind my pain,” the 25-year-old wrote on Instagram.
“As I have started treatment, I am looking forward to embracing this next challenge in life.
“Without a doubt, every healthy day is a gift and I am one hundred percent committed to keeping strong and continuing to battle on and off the tennis court.”