Greek tennis star Stefanos Tsitsipas is all too aware of the threat Coco Gauff poses as she prepares to take on his girlfriend, Paula Badosa, at the Australian Open. The women’s duo will face off in the quarter-finals of the Melbourne major on Tuesday, reuniting after meeting twice in 2024.

The opening match of the quarter-final schedule promises to be one of the best on display. And Tsitsipas has already sent a firm message acknowledging Gauff’s skills in the past.

The American youngster is seeking her second major title in Melbourne after opening her Grand Slam account at the 2023 US Open. And Tsitsipas has been appraised of her quality for years, having first lauded Gauff’s threat when she was just a youngster.

“She has soul, she has the biggest fighting spirit I’ve seen,” he said of Gauff during an Instagram Q&A in 2020. “I’ve played with her back when I was 16 years old, and I can tell you I was impressed.”

The Greek star only entered into a relationship with Badosa in May 2023, and save for a brief split the following year, the pair have been largely inseparable since. But it seems he’ll be among those stressing the threat his partner is about to face Down Under.

By his estimations, Gauff was just 10 years old when she went up against Tsitsipas on the practice court. And even then it was evident she was destined for big things. His comments will serve as a warning to Badosa, who herself knows all about the American’s grit, having been on the receiving end of her comeback victories.

Badosa, 27, and Gauff, 20, have squared off on six occasions to date, and each boasts an even split of three wins apiece. The former did hold a lead in their budding rivalry until last year when Gauff beat her twice in as many meetings.

And Badosa was left kicking herself on both occasions given she clinched the opening set at each turn before folding. Her first collapse took place in the last 16 of the Italian Open before she then succumbed in the semi-finals of the China Open.

There’s also nothing to separate the two stars when it comes to playing surface, having each won two matches apiece on hard courts. But one is destined to take the advantage come Tuesday, and Gauff will be looking to move ahead in their head-to-head record for the first time.

This is the third time Badosa has reached the last eight of a major tournament, though she’s yet to make it into the semi-finals of any Grand Slam just yet. And Tsitsipas – who suffered a shock first-round defeat in his own Australian Open campaign – will be courtside for every swing in the hopes she can celebrate a career first against a foe he has long respected.