Watch: Coach Patrick Mouratoglou explains why Serena Williams's serve is so precise

Patrick Mouratoglou, who has been Serena Williams's coach for nearly 10 years, posted a coaching video on his Instagram handle on Monday. In the video, he can be seen giving a budding player some tips to improve his serve.

Patrick Mouratoglou and Serena Williams have one of the longest coach-player partnerships on the women's tour in recent history. The pair have had a fruitful partnership since they first joined forces in 2012, with Williams winning 10 Major titles under the Frenchman's tutelage.

Mouratoglou has also notably coached World No. 4 Stefanos Tsitsipas, American teenager Coco Gauff and 2006 Australian Open runner-up Marcos Baghdatis.

Mouratoglou often uploads coaching clips on Instagram, and his most recent video showed him personally training a youngster at his academy.

In the video, the Frenchman can be seen working on an amateur player's serve while laying out some important tips to follow for a precise first serve.

Mouratoglou asserted that to have a precise serve, one must decrease the range of their ball toss during the first serve. The Frenchman then illustrated his point by drawing a comparison between Serena Williams and Maria Sharapova.

The American is one of the best servers on the women's tour. Her lethal first serve has been an important component of her game and brought her great success. Sharapova also had a powerful serve. But she lacked consistency and served tons of double faults.

"It looks silly but the best players in the world can track their toss. They keep it in a zone like this," Mouratoglou says to the player. "How Serena does it is amazing and Sharapova [on the other hand], who's really tall but doesn't serve that well for her height."

Mouratoglou added that it is important for players to keep their toss consistent and not constantly alter the position of the toss.

"They analyzed her toss and in width, it's two or three times more [than Serena]. Her ball tosses are more random, in depth too. As soon as you need to adapt, you'll hit more bad serves. The majority of tosses either happen here (points left) or here (points right)."

"Look at Serena Williams on the serve, the arm goes at the speed" - Patrick Mouratoglou's tip to a young player

2021 French Open - Day Two

Patrick Mouratoglou also asked the player to toss the ball slowly just like Serena Williams normally does. The video then cuts to a short reel of the American practicing her first delivery to show how it's really done.

"Look at Serena on the serve, the arm goes at the speed. You can toss very high and very slow. Look. You don't need to do an abrupt movement, the more abrupt, the less precise it is. Like this, at this speed. Very slow with your arm," Mouratoglou says.

Lastly, Mouratoglou asked his ward to hold his arm out in front and open up his palm while he tosses the ball during the serve.

"Hold it here and open your hand. You really have to open or otherwise, your fingers will have an impact on the ball and every time it's different. Take the ball like this and open your hand. Instead of guiding your hand, you open."