Sep 11, 2025 12:32 PM EDT
Serena Williams and Patrick Mouratoglou formed one of the most successful player–coach partnerships in tennis history. Over the course of more than a decade together, the pair collected 10 Grand Slam titles, a WTA Finals crown, and returned Serena to the world No. 1 ranking. Their collaboration was marked by dominance, and a flair for rewriting the limits of what was possible in women’s tennis.
However, after Serena’s return to the tour following the birth of her daughter in 2017, the two parted ways in 2022. At the time, speculation swirled about the reasons behind their split, with many pointing to Serena’s struggles with fitness after childbirth. Now, Patrick Mouratoglou has confirmed that those rumors carried truth.
In a recent interview with The Guardian, the French coach explained candidly that weight and fitness concerns were central to the decision.
“It was after the pregnancy – not right after; I know these things take time,” Mouratoglou said. “I told her: ‘Listen, this is not a comment on how you look. It’s not my problem.’ But tennis is a sport in which you can’t afford to be overweight.”
“First of all, the pressure on your joints and everything is so big that your chances become much higher,” he explained. “The second thing is it’s a sport in which you change directions all the time and with a lot of speed. Even one kilo overweight is a lot. When you go full speed in one direction with one kilo extra and then need to stop and come back, the time that you lose is really important.”
Patrick Mouratoglou, coach of Naomi Osaka, looks on during the first day — Source: © Jayne Kamin-Oncea-Imagn Images
Mouratoglou’s remarks shed light on the physical demands of elite tennis and the razor-thin margins that separate victory from defeat at the highest level.
“In Serena’s case, she was older – so of course the body is not going to bounce back the same as before, and the risk of injury is even bigger,” admitted the Frenchman. “We had a few fights about it. I remember she did not like when I said that because she thought I was judging her.”
“But I kept telling her, I don’t care about your look. It’s not my job. My job is your tennis. If you want to come back to the top and make history, then we have to be very efficient on every level – including this one, which for me was the key element.”
Their split marked the end of an era, but the legacy of their partnership remains undeniable. Together, Williams and Mouratoglou set the bar very high for a coach-player success curve.
About the author
Tennis Writer, Athlon Sports
Vivek Devane has followed tennis for over two decades, including nearly 10 years as an analyst. He has earned exclusive interviews with top ATP and WTA athletes on the tour and attends various press conferences.