Serena Williams has been dealing with the same knee problems as Rafael Nadal recently, her coach Patrick Mouratoglou said at the BNP Paribas Masters in Paris on Tuesday afternoon.

Williams’ Decision to End Her Season Prematurely Due to Injuries

After suffering a surprise loss to Roberta Vinci in the semifinals of the US Open, Serena Williams decided to end her season prematurely, citing injuries and fatigue. “It's no secret I've played injured most of the year — whether it was my elbow, my knee, or, in the final moments after a certain match in Flushing, my heart,” Williams said in a statement released on the China Open website. “This is a very difficult decision, but one ultimately made because of the love of the game.”

Williams’ withdrawal was no surprise considering it was clear that she lacked motivation after a stressful two weeks in New York where all the attention was directed to her. She was just two wins away from completing the Calendar Grand Slam, a feat that had never been accomplished in 27 year. Williams was undoubtedly the favourite to win this tournament and because of the expectation and stress that had built up over the course of the year, the world number one found it difficult to even find motivation to pick up a tennis racquet ever since her US Open heartbreak.

Because of this, the American took a two month break from tennis, and returned to practice for the first time in nearly two months at Mouratoglou’s tennis academy in Paris. It was there when they realized Williams’ knee problems, and advised her to take a break in order to stop aggravating the injuries.

Mouratoglou Reveals Williams’ Knee Problems

“It’s the same as Rafa. It’s just playing for so many years, the cartilage is [almost] gone. Not all of it, but a big part, so the bones just hit themselves,” Mouratoglou said. “She has bone bruises, and if you keep on playing with this for too long, too much, the next step is a stress fracture.”

“There was no other option, and we knew that at some point we had to [stop], because she plays with pain all the time. I’m not a doctor, she has treatment, but I know without rest there is no chance because you keep on hitting the bones all the time.”

“With the knees you never know, sometimes the pain is much more [than on other days]. That was the first thing she said when she came to the practice court: ‘My knees hurt so much today.’ So she was really struggling to move.”

When asked about whether or not he was worried about Williams’ preparation for the 2016 season, Mouratoglou said she was excited to get back on the court but she will have to manage her motivation during a long pre-season training block.

“If you go too fast then the last weeks before the tournaments, you’re going to go down, and that's the moment when you need to go up, so you have to manage it. I’m happy to feel her so excited. I told her to calm down.”