Kaja Juvan won the battle of the qualifiers at the Australian Open to book her place in the third round, defeating Egypt’s Mayar Sherif in a match that pushed both players to the limit to set up a showdown with No. 22 seed Jennifer Brady.

The 21-year-old Slovenian fought back from a set down to beat Sherif – who made history for her nation by reaching the second round – before overcoming two bouts of sickness to close out a 3-6 7-6(2) 6-3 win in two hours, 39 minutes – the second-longest women’s match of the tournament so far.

“Long match today,” she wrote in an understatement on Instagram. “So grateful for all the support. It's so nice to play with the crowd again. Definitely helped. Can’t wait for Saturday.”

Juvan was one of 15 players to receive an ITF Junior Player Grant in 2018, designed to provide a financial boost to players in their transition from the junior ranks to the professional game.

And the 21-year-old, a two-time gold medallist at the Youth Olympic Games and 2017 Wimbledon girls’ doubles champion, is returning on that promise with her first appearance in the third round of a major.

Juvan, ranked No. 100, has never faced Brady before, and is entering uncharted territory on her second main-draw appearance at Melbourne Park. And while she faces a race to recover in time for Saturday’s encounter, 2020 US Open semi-finalist Brady will no doubt be relatively fresh after easing past American compatriot Madison Brengle 6-1 6-2 in just 52 minutes.

But it was the demise of another American that grabbed the headlines in Melbourne as reigning champion Sofia Kenin was dispatched 6-3 6-2 by Estonia’s Kaia Kanepi.

“She obviously played well,” said Kenin, who shed a tear as she admitted to struggling with the added pressure of returning as champion. “I obviously felt like I couldn't find my rhythm. I was obviously way too nervous. She came up with some good shots. She obviously had a good plan against me. I just couldn't execute my shots.

“I know I couldn't really handle the pressure. I'm not obviously used to this, so right now I just got to figure out how to play at that level that I played at. Because like today and those matches, it just hasn't been there.”

Kanepi, formerly ranked as high as No. 15 in the world, has a history for upsets at the majors. The 35-year-old is 7-6 against top-10 opponents since 2010, compared to 5-29 on the WTA Tour.

“I was nervous too,” Kanepi said with a laugh. “I had to calm myself down and then I had no time to look how the opponent is feeling or doing… I played good today, I served really good and I think it was a good win.”

Elsewhere there were wins for top seed Ashleigh Barty over fellow Aussie Daria Gavrilova 6-1 7-6(7), No. 6 seed Karolina Pliskova against Danielle Collins 7-5 6-2, and No. 5 seed Elina Svitolina, who beat Coco Gauff 6-4 6-3.

Belinda Bencic, the No. 11 seed, fended off Svetlana Kuznetsova 7-5 2-6 6-4 to set up a third-round showdown with former Australian Open semi-finalist Elise Mertens, who beat China’s Lin Zhu 7-6(8) 6-1.

One unseeded player is guaranteed to reach the fourth round after USA’s Jessie Pegula and Kristina Mladenovic of France advanced to face one another after straight-sets victories.