Who is Nick Kyrgios' girlfriend? Meet Ajla Tomljanović.

On Monday night, after a convincing win against world No.98 Rogerio Dutra Silva in the very first round of the Australian Open, Nick Kyrgios sidled over to give his post-match interview on court.

Of the many questions thrown his way, one touched on the preparation that comes in the week before a big grand slam.

“I had a pretty hectic week, it’s been good, I had my girlfriend’s company in the room so it’s been alright,” the world No. 17 said, a sly grin emerging the moment he realised the suggestion that came with his comment.

Predictably, the crowd cheered.

So who is Kyrgios’ girlfriend in question? Among the news of his sporting prowess and occasional bratty tendencies, little is known of his inner social circle.

Twenty-four-year-old Croatian-born Ajla Tomljanović has been with the Australian tennis star for the last two or so years.

Born and raised in Zagreb, Tomljanović is a professional tennis player herself, having first picked up a racket at the age of seven.

In 2014, it was announced that Tomljanović would take Australian citizenship and begin competing for Australia at the 2014 US Open. Just weeks before last Christmas, she underwent a citizenship test in her home city of Brisbane.

“I did the ceremony in Brisbane, actually, after I played, so that’s why it still said Croatia,” Tomljanovic recently told News Corp.

“It was actually so cool. I didn’t really know what it was going to be like and I had to pledge and everything. It was a cool experience.”

Currently, she is ranked number five in Australia and number 136 in the Women’s Tennis Association worldwide rankings, bowing out of the first round of the Australian Open in straight sets, losing to former French Open finalist Lucie Safarova.

A post shared by Nicholas (@k1ngkyrg1os) on Dec 20, 2017 at 5:53pm PST

It is, however, one of Tomljanović’s first forays back into the professional circuit after suffering a shoulder injury for all of 2016, and much of 2017.

Though very little is known of the woman who is closest to one of our most well-known tennis stars, it’s certainly not the first time Tomljanović has found herself in a headline or two in association with the controversial ways of her partner.

In July last year, Tomljanović’s name was unwittingly pulled into news stories about Kyrgios, his partying ways and whether the duo were still together. After losing in the first round of Wimbledon, Kyrgios was pictured with two women – Monique Belovukovic and Chelsea Samways – at Cirque Le Soir nightclub in Soho, London.

Backlash was swift and inevitable. Some found the partying unnecessary and unprofessional, given his less-than-stellar performance on court and the simple fact it wasn’t his off-season. Others despaired for his girlfriend… after all, where was Tomljanovic, while her boyfriend was snapped in a less than flattering light with two other women?

In the days after, Tomljanović deleted any mention of her boyfriend from her Instagram account, such is the modern-day version of a public dispute. It was rumoured the couple had split.

However, some six months later, it appears Kyrgios may have done something right, with the couple back together and regularly posting photos together on the platform.

Couple this with the general sense that Kyrgios’ behaviour seems to have improved – and the 22-year-old himself appearing to have mellowed – and you could argue something is remarkably right with Kyrgios’ inner-circle right now.

Who knows how much Tomljanović has had to do with that.