If any milestone could top a first Grand Slam quarterfinal, it’s arguably beating a former champion along the way.
Ash Barty and Stefanos Tsitsipas have achieved both at this Australian Open – and having thrilled fans throughout the world with empathic arrivals, each aims to carry that electrifying form into bigger breakthroughs at Melbourne Park.
Barty entered unchartered career territory with victory over Maria Sharapova in the fourth round, her three-set victory over the 2008 champion making her the first local woman to progress so far at the Australian Open in 10 years.
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The sports-mad Australian public is naturally abuzz – but it’s not only the locals who are catching on to Barty’s modern take on a classic style. “(It’s a) different style, but a really tough style to play against,” Sharapova conceded. “I thought she played a really great match.”
Doing so opens up many delightful possibilities for the popular Queenslander.
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“I love to play with freedom and fun and try and create as much variety as possible. Obviously, my game is built around my serve and forehand and bringing in a variety with the slice,” Barty said.
“But there are no secrets in tennis. I think every day I try and challenge myself to add another string to my bow in a sense and try and become the complete player. I think that's my biggest goal.”
A first Grand Slam semifinal now requires another first from Barty, who is yet to win over quarterfinal opponent Petra Kvitova in the three matches they’ve played. The most recent was in the 2019 Sydney decider, when Barty pushed the two-time Wimbledon champion to three hard-fought sets.
Asked what she’d do differently a week-and-a-half later, the down-to-earth Aussie related a simple plan: “Win a couple more important points, I suppose, yeah, compared to Sydney.
“It's exciting that I get to have another chance at Petra straightaway. Not often does that happen where you get to kind of have a replay against the same opponent.
“(I’m) really pumped to have another chance here.”
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Tsitsipas – and his singing band of supporters – are equally charged.
Fearless as he defeated six-time champion Roger Federer in the fourth round, Tsitipas is determined to maintain momentum against Roberto Bautista Agut in their first tour-level match.
“For sure it's a good win against Roger. I mean, we all know who Roger Federer is, what he has done in tennis,” said Tsitsipas of defeating his childhood idol. “But I still have to keep my focus, keep my concentration on further goals that I want to achieve. That's a very good beginning. I need to stay humble.
“This win is a good milestone, let's say (a) good first step to something bigger.”
It takes a level head to maintain focus on the bigger picture but the 20-year-old Tsitsipas, playing only his second Australian Open, is showing wisdom beyond his years.
“I do feel like my game is pretty good at the moment. I feel confident,” he said. “That's very important. I'm really pumped and excited to be competing in the quarterfinals.”
Tsitsipas will need all that positive energy against another first-time major quarterfinalist in Bautista Agut, who defeated AO2018 runner-up and 2014 US Open champion Marin Cilic in the fourth round.
It was Bautista Agut’s fourth win over a Grand Slam champion already this season, with a ninth career title in Doha secured with victories over Stan Wawrinka and Novak Djokovic, and a first-round win over Andy Murray at Melbourne Park.
“These players obviously are different than any other player. You need something extra to beat those players,” Tsitsipas said. “But if I manage to keep the same levels of concentration like I did today (against Federer), same patience, same mental toughness, willing to fight, I'm pretty sure it's going to go pretty well.”
Danielle Collins also takes her fast-growing self-belief into a maiden Grand Slam quarterfinal, where she meets first-time opponent Anastasia Pavlyuchenkova.
A year ago, the 25-year-old Collins lost in AO qualifying; her fourth-round win over Angelique Kerber, the 2016 champion, on Sunday marked the American’s third top-20 win in the first Australian Open main draw of her career.
“I think I've definitely made improvements. I also think that at the end of the day tennis is tennis,” said Collins, who thrived in US college tennis before turning her attention to the professional tour.
“Everybody gets their shot at the pie. Right now, I'm certainly getting mine.”
Frances Tiafoe is another young star contesting a first Grand Slam quarterfinal, with Sunday’s four-set win over Grigor Dimitrov earning a milestone meeting with Rafael Nadal.
It’s new territory in every sense for the 21-year-old American, who is yet to compete against the superstar Spaniard. The potential for another Next Gen star ousting a former AO champion is clear.
From thrilling firsts come new possibilities – and as AO2019 is emphatically demonstrating for some fast-rising players, the hint of even bigger things to come.