He rubs the sweat off his face and throws the ball in the air … before catching it and starting over. His pre-serve routine needed to be flawless, and he’d forgotten to swipe his nose a second time.

Naomi Osaka has had an exhausting week on clay, but she found a way to be her jovial self with a light-hearted tribute to Rafael Nadal following her recent title win in Saint-Malo, France. The ...

In Nadal's case, developing a powerful serve is critical given the punishment he exacts on his body, particularly his knees, as he thunders around the court retrieving ball after ball.