Who is Coco Vandeweghe?

Coco Vandeweghe made her first Grand Slam semifinal on Tuesday after beating seventh-seed Garbine Muguruza. FOX Sports Asia takes a look at the fiery American making waves at the Australian Open.

Vandeweghe produced one of the shocks of the Australian Open when she knocked world number one and defending champion Angelique Kerber in the fourth round.

Then in the quarterfinal she did it again, downing Garbine Muguruza, the reigning Roland Garros champion scoring just 10 points in the second set as she was thrashed 6-4, 6-0.

Her heroics have left many fans asking exactly who she is.

She is the product of an athletic dynasty on her family’s maternal side.

Her mom, Tauna, was an Olympic swimmer while her grandfather Ernie was a guard for the New York Knicks between 1949 and 1956. Her uncle Kiki, an NBA All-Star, also played for the Knicks as well as coaching the New Jersey Nets.

Another uncle Bruk, won a medal in beach volleyball at the 1994 Goodwill Games, while her Aunt Heather was captain of the US women’s polo team.

“In my family, you have to learn how to throw a football or get tackled harder than you probably want to,” she says. “[Kiki] wasn’t going to be merciful when we thought we could beat him at Horse.”

Hittin' the dab into the quarterfinals! ????? #NoCarbsAfterThree #Quarterfinals #AusOpen

A photo posted by CoCo Vandeweghe (@cocovandey) on Jan 22, 2017 at 6:45am PST

She’s also a fiery character who has been known to smash the odd racquet, and is not afraid to speak her mind – traits that recently lead her to be referred to as “the Ronda Rousey of tennis” by the Observer newspaper.

It was her grandmother Colleen Kay Hutchins, a former Miss America, that taught Vanderweghe her most important sporting lesson.

“My grandmother always told me: ‘Fake it till you make it,’” Vandeweghe said at Wimbledon in 2015. “Coming from a Miss America that basically had to ooze confidence, that’s a pretty good line.”

It’s a mantra that Vandeweghe repeated often after her defeat of Kerber.

“When you play tough players, like you will in later rounds of tournaments you can’t be showing that you’re struggling or not feeling confident in yourself. At least that is what I decided to tell myself this year and also last year, a lit bit because I was lacking in confidence in certain tournaments and certain stages. Last year I came here and didn’t even win a match. So here I am now.”

“Well, I guess I faked it a lot because I was feeling like crap out there. But, you know, fake it til you make it and you have got to keep out there and keep playing and just hope for the best and my game plan was to execute knowing that she was going to get a lot of balls back and you know, just to keep picking my spots and trust my game to beat her and it did today.”

Right now, the 185cm tall 25-year old, says she’s too busy for a relationship, but she still has strong views on the kind of man she wants.

“A guy has to be taller than me,” she says, although she’d make an exception for actor Scott Eastwood. “I looked it up on Wikipedia — he’s [5-foot-10]. I stalk his Instagram.”

Off court, Vandeweghe loves reality TV.

“I grew up with [NBA legend] Bill Walton coming over to my house. I saw the best athletes in awe of my grandfather,” she says. “I don’t get awe-struck with athletes. I get awe-struck with trashy TV people.”

On court, she’s not afraid to speak her mind.

Back in 2015 at Wimbledon, Vandeweghe made the headlines after she told Maria Sharapova to stop moving so much while she was about to serve.

She was also allegedly once involved in a fiery exchange of expletives after Yulia Putintseva accused her of being a serve-only player.

Putintseva later told her: “I won’t say I didn’t say that. But it happened right after when she told me that I am a f****** b**** who doesn’t know how to play tennis at all, and that my father is so stupid, and she started bull******** me.”

Vanderweghe’s reply?: “Being American and being obnoxious a little bit, I was like, ‘Well, I’m an American, so I have freedom of speech.”

Then there is the time she clashed on court with Donna Vekic at the 2015 US Open.

“Well, if I really bumped into her, and I meant to do it, she would be on the ground,” said Vandeweghe. “I mean, it’s just trying to make something out of nothing, which is fine, but I miss that kind of feistiness and confrontation of when I could play a physical sport.”

Quizzed about her fiery temperament, Coco says: “I’m definitely not shy in that way.

“I’ve never been someone to back down from any sort of confrontation; I almost look for those sorts of confrontations in my own life today. I think I’ve gotten better at it, but what I think is right is what I think is right.

“If I think someone on the outside is doing me wrong, I’m not going to be shy about it and get pushed to the wayside because I think I should keep my mouth shut. I’m my own person, you know?”