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Mouratoglou has been Williams' coach for five years

Williams has won 10 grand slams with Frenchman

CNN  — 

Patrick Mouratoglou likes stress. He craves it. The man Serena Williams credits for taking her from “great to history” is not one to rest. He can’t. Boredom would quickly smother the Frenchman were he to ever take it easy.

The 47-year-old’s pulse used to quicken when he would watch Williams, one of history’s greatest champions, compete. That was pressure. That was adrenaline. He loved it.

But with his pupil on maternity leave, deep into her third trimester, the coach has to now find the buzz, the rush, from elsewhere, though nothing can truly compare to helping Williams rewrite the record books.

Even live television interviews do not make the heart race, for the Parisian is as comfortable on screen as the rest of us would be sunbathing on a beach.

“You can check my pulse before and after, I am the same,” he says, fresh from a live appearance on a British breakfast television programme.

“I find a way to have stress because I need it. I did TV during the French Open and I told the guy ‘make me do things I’ve never done before.’”

Mouratoglou and Serena share a joke.

This summer marks his fifth as Williams’ coach and so, naturally, he has become accustomed to the attention that comes with working alongside the world’s most recognizable female athlete, a player who has danced in a Beyonce music video and been a tennis superstar for almost two decades.

Once describing being afraid as a “disaster,” Mouratoglou also has no fear, which was a useful trait when confronted by Williams’ father, Richard, shortly after the 23-time grand slam champion had appointed the Frenchman as her coach.

Never before had the American worked with someone not sanctioned by her family. The father, the engineer behind Serena and sister Venus’ success, needed to be swayed. He was quickly converted and Williams’ decision to broaden her horizons proved to be a masterstroke.

Mouratoglou can list Williams’ achievements since their partnership began as easily as someone ordering takeaway from a favorite restaurant: 10 grand slam titles, two Olympic golds and a three-and-a-half year stint at the top of the world rankings.

But both he and Williams, he says, are the same characters they were before their alliance.

“I don’t think she’s changed me or I’ve changed her,” Mouratoglou, who describes himself as a person of extremes, tells CNN.

“I have more exposure clearly than before, but it’s also deserved because we did so well.

“When you’re with Serena you have a lot of exposure, people look at you different, probably. I’m not saying that they should, but it’s a normal process.”

Serena works on her forehand.

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‘Serena with a baby is still Serena ‘