Wimbledon 2019 news - Why 15-year-old Coco Gauff is the story of Wimbledon

Across the net, her Slovenian opponent served bombs and smothered her with a nous only acquired from a professional career that began when Gauff was 3 years old. She stared to her support team of her parents, coaches agents in anguish.

When Gauff faced Hercog’s first match point at 3-6 2-5, she saved it in the most improbable manner - with a low slice winner that fizzed on the ground and curled away from the court. The match wore on and Gauff stopped swinging hard and simply dug in, relying on her defence and movement. She simply put balls into the court, contorting her body as Hercog tried to wrong-foot her and chasing every last ball down. She broke back for 5-5 and eventually a supreme tiebreak, pushing the match into a third set and eventually winning 3-6 7-6(7) 7-5.

Nobody could have ever imagined those scenes 10 days ago, yet with the exception of the Rafael Nadal and Nick Kyrgios match, this first week at Wimbledon has been almost entirely defined by Gauff’s breakthrough. The court scheduling said it all - this match pitted the world number 313, from the United States, against the 60th ranked Hercog, yet it was played on Centre Court. It could have been the first round of a lowly WTA event. Instead, as Henman Hill filled to the brim and the line of ticket resells wound on unendingly, the crowd gave standing ovations and willed the 15-year-old to victory.

There was every chance that Gauff wouldn’t have made it this week. Until four days before her first qualifying match, she even didn’t know what she was doing. Gauff’s team had sent an application to Wimbledon for a wildcard into qualifying, an event held four miles away in a field in Roehampton. Gauff trained for weeks in Florida knowing that she would imminently be going to Europe but not knowing where. If Wimbledon rejected her, she would have gone to France for a gala at the Mouratoglou Tennis Academy, so she spent her time buying dresses for the event.

When she found out, she jumped on the next plane to London and began playing against many players who had already honed their grass skills for three weeks. She said during that week that she was constantly falling, still trying to find her footing on a strange surface. But each time she got back up and won, destroying the field and escaping Roehampton without losing a set.

Tennis has seen a long list of prodigies and the great benefit of being young is that they are too young to know any better. Long before they face the harsh realities of sport, players burst through the door with a recklessness, able to channel their talent without the obstacle of pressure.

Gauff’s talent is immediately clear. Her first serve has already scaled 117mph this week and she is perhaps serving better than any young teenager in history. She also moves like the wind and her backhand sears through the grass. But this week has been as significant because of the mental fortitude that has backed up her gifts. The American could incessantly bludgeon the ball if she likes, but she hasn’t. She has played with restraint throughout, looking to build points and choose the right opportunities to ratchet up the point. To be able to think, analyse and be intelligent against players who know so much more than her takes a whole other level of precocity.

Gauff noted during qualifying that she had only really just started to incorporate slices into her game, yet in the middle of Centre Court, she spent much of the match knee deep in long, endless slice rallies - rallies she often won. “I want to thank my coach, JC, for making me do all those slice drills,” she said, laughing afterwards. “He knows I hate them. But it came in handy today. Also thanks to Courtney for slicing today in my warm-up because I was, like, ‘Just hit the ball.’ He's like, No, I'm slicing. Thank you.”

Off the court, the 15-year-old is young in some respects and far from it in others. She is a Jaden Smith superfan who frequents Instagram Live after matches, but she is also a rare player who has made it clear that she wants to have an influential voice off the court. Gauff has a supreme confidence in her ability and was underlined by her morbid motto earlier in the week. “Just wing it,” Gauff says. “This is kind of a sad thing, we're all going to die one day, I just want to make the most of it.”