The fascinating story of Mirka, the woman behind Roger Federer.

Even those who don’t particularly enjoy tennis will delight in the name Roger Federer.

The Swiss player is currently ranked number two in the world, with 19 Grand Slams under his belt. After tonight’s semifinal match at the Australian Open, he could be one step closer to taking that total to 20.

The name Miroslava (Mirka) Federer might not be quite so familiar.

The pair married in 2009 and she’s been a constant at all of his matches and tournaments since well before then, now often seen in the player’s box with the couple’s four children, identical twin girls, Myla Rose and Charlene Riva, eight, and twin boys Leo and Lenny, three.

But their relationship and partnership, both professional and private, dates back far further than that. And Australia has always played a special role in it.

In January 2002, Roger Federer and Slovak-born Swiss tennis player Miroslava "Mirka" Vavrinec paired up to play the Hopman Cup in Perth. It was their first (and last) time playing publicly together, but it wasn't the start of their relationship as many presume.

"It didn't quite start it here, it actually started at the (2000) Sydney Olympics, also in Australia, but that was almost one and a half years earlier, so we were already a rock-solid couple and we had a great time," Federer told Tennis World USA.

"We spent two weeks together, that's how we got to know each other and on the last day before we left, we kissed for the first time," he's said of the first time they met.

As for the match: "It was slightly awkward playing with your girlfriend at the time, but we got through it and had a good time after all... [It was] awkward for me, she was cool about it because she's older than me so she had experience."

Born in Slovakia in 1978, Vavrinec emigrated to Switzerland when she was two years old. When she turned nine, her father took her to watch a tennis tournament in Germany where she met former Number one Martina Navratilova, who suggested she try the sport. Later, Navratilova reportedly sent her her first racquet and arranged a tennis lesson for her.

Years of training and international tournaments followed before she competed in her first Grand Slam at the 1999 French Open, exiting the first round. In 2000, she played in the Australian Open, French Open and Wimbledon, as well as the Sydney Olympics.

She cracked the top 100, reaching a career-high WTA singles ranking of world No. 76 on the 10th September 2001. That year, she also made it to the third round of the US Open.

However, a persistent foot injury ended her career early, retiring from the game in 2002, not long after competing at the Hopman Cup with her future husband.

"Unfortunately, she was quite hurt [during that tournament], that's why then she ended up being retired at a too young of an age," Federer has said.

Unable to play the game she loved, Mirka became involved in other ways, including becoming Federer's public relations manager, handling much of his media affairs.

Since then, she's played a "huge role" in Federer's career and success.

"She understands the big picture extremely well and does a great job in terms of letting us work but also shares invaluable information," Federer’s former coach Paul Annacone has said.

"This is a tricky balance. She’s been there since day one, so she knows very well what it takes and how to get there."

And the person who is most appreciative of all her support and sacrifice is Federer.

"Without her I couldn’t do it," he said in a press conference after Wimbledon last year.

"If she said, you know, I don’t want to travel no more, I’ll say, Okay, my career is over. It’s as simple as that. So she’s the key to a lot of this.

"But she’s happy to be doing it, not on a weekly basis just because the traveling gets too much with the four [children].

"I’m happy she allows me to chase our dreams really, because she’s in it as much as I am, even though she’s more on a different side right now."

As Federer takes on 21-year-old Chung Hyeon tonight in his Semi-Final, you can guarantee Mirka will be there, cheering loudly from the sidelines.

LISTEN: Should we be sympathising with Australia's troublesome young tennis stars? We discuss on Mamamia Out Loud.