Who is Danielle Collins, the fearless American through to Australian Open semi-finals?

Danielle Collins has reached her first grand slam semi-final at the Australian Open and will take on two-times major champion Petra Kvitova for a place in Saturday's final.

Who is the American and how has she progressed to this point?

The college background

At 25-years-old, you might wonder why world No 35 Collins has only now made her breakthrough at a grand slam.

The right-hander turned professional in 2016 after graduating from the University of Virginia at 22 with a degree in media studies and a master's degree in business. Collins took the viewpoint that if tennis didn't work out, she needed a backup plan.

Even after winning her first National Collegiate Athletic Association (NCAA) singles title in 2014, Collins could not be persuaded to side-step her studies and pursue tennis full-time.

"It costs over $50,000 to go to UVA," she once said. "And I was really happy being on a team, being in the classroom."

She even declined a cheque of $35,000 for a first grand slam appearance at the 2014 US Open in order to maintain NCAA eligibility and her tennis scholarship.

It was a good call. Two years later she won a second NCAA singles title and finished her college career in 2016 as the top ranked collegiate player.

Making breakthrough in 2018

Collins lost in the final round of qualifying at last year's Australian Open, but it was during the 'Sunshine Swing' at Indian Wells and Miami that she gave notice of her talents.

Born in Florida, playing on home turf clearly suited Collins and she backed up her first WTA tour win over Taylor Townsend by stunning world No 14 Madison Keys in straight sets en route to the fourth round at Indian Wells.

She went even further in Miami. After coming through qualifying, the 5ft 10 in baseliner saw off CoCo Vandeweghe and Donna Vekic before registering her biggest win of her career against seven-time grand slam champion Venus Williams to reach the semi-finals where she ran out of steam against Jelena Ostapenko.

Her spring uprising saw her leap from world No 160 to No 45. Collins' elevation continued in July with a run to the last four at San Jose on her favoured hard courts for a career ranking high of No 35.

A sense of belonging

It wasn't until Collins' stunning first-round win over 13th seed Julia Goerges that she experienced the winning feeling at a major at the sixth attempt.

Now there is no stopping her. Not that Collins is surprised. After demolishing world No 2 and much fancied for the title in Melbourne, Angelique Kerber, for the loss of two games, Collins boldly said there was more to come.

"I may not have won a grand slam match before this week," she said immediately after dismantling Kerber, "but I gotta tell you, I think it's gonna keep happening."

It is rare for a player, especially in the women's game, to speak so matter-of-factly and with such confidence.

But coming through college tennis, where the environment is loud and crowds can be hostile, has given Collins the grit and backbone which makes her a terrifying and unpredictable opponent.

"I love making it kind of a war," Collins has said this week. "I love when things get competitive. Whether people are for me or against me, I'm not really fazed by it. I kind of like it more when people cheer against me because I want to prove them wrong."

A fearless style

Collins backs up her no-nonsense demeanour with her ferocious hitting on court.

The American is an excellent mover and combined with her lights-out tennis, makes for an entertaining watch.

"She's very tenacious," One of Collins' coaches Mat Cloer said in Melbourne after her win over Kerber.

"She wants to win at everything. That's a massive quality she has and it's nothing against the girl on the other side of the net. She likes to fight and it's something we encourage her to do. Be yourself. Don't hide anything. It's fun to watch."

Tenacity and determination have been drummed into her from an early age after being introduced to the sport by her father Walter, a former commercial fisherman who is now a landscaper.

“My dad’s 80 years old and still goes to work every day,” Collins said. “He’s the hardest worker I know.”