From Tennis Phenom to “Seeing Two Balls”: Exploring Monica Seles's Health Story

For years, Monica Seles was the brightest light in tennis. A teenage prodigy from Yugoslavia, she had a game unlike anyone else — two-handed strokes on both sides, fearless line-painting shots, and the kind of mental grit that could shake even the most seasoned opponent. By the time she was 19, Monica had already won seven Grand Slam titles and spent 91 straight weeks as the world No. 1, reaching the finals in nearly every tournament she entered, according to The Athletic.

Then, in April 1993, the unthinkable happened. While leading a match in Hamburg, Germany, Monica was stabbed in the back by a spectator who idolized her rival Steffi Graf. She later described how the attack shattered her sense of safety on court. After more than two years away, she returned to win the 1995 Canadian Open and, soon after, the 1996 Australian Open — a comeback that became one of the sport’s most inspiring chapters.

She eventually retired from full-time competition in 2008, still appearing in exhibitions and mentoring younger players. After years of staying active in public life, a private health challenge began to shape her world. Today, Monica Seles’s health has become the focus of a deeply personal new chapter.

Since 2019, Monica had largely stepped out of the spotlight. That year, she began noticing strange symptoms — sudden muscle weakness in her arms and legs, and, most alarmingly, double vision while playing tennis.

“I would be playing with some kids or family members, and I would miss a ball. I was like, ‘Yeah, I see two balls,’” Monica told The Associated Press, as documented by The New York Post.

“These are obviously symptoms that you can’t ignore. And, for me, this is when this journey started. And it took me quite some time to really absorb it, speak openly about it, because it’s a difficult one. It affects my day-to-day life quite a lot.”

Getting a diagnosis was far from quick. As the COVID-19 pandemic unfolded, medical appointments were harder to come by. Her doctor referred her to a neurologist, and after nearly two years of tests and scans, she learned she had myasthenia gravis — a rare autoimmune disease that disrupts communication between nerves and muscles.

According to experts cited by The Athletic, myasthenia gravis affects an estimated 150 to 200 people per million worldwide. Its symptoms, which include double vision, muscle weakness, and fatigue, often come and go. This unpredictability makes the disease difficult to diagnose, and there is no cure, though treatments can help manage it.

For Monica, receiving the diagnosis was another kind of “reset” — the same mental approach she once used between points, games, and matches. Throughout her life, she’s been forced to reset in bigger ways: leaving her home country, recovering from the 1993 stabbing, and adapting to a chronic illness.

Monica’s health journey is only the latest chapter in a life defined by overcoming the odds. She’s not just appreciated for her dominance on the court, but for her ability to face each setback — from an unimaginable act of violence to an invisible illness — with determination. By sharing her story, she’s hoping to help others spot the signs of myasthenia gravis and seek help sooner.