The list of things the tennis world has yet to learn about Lulu Sun is long.

The journey of the 123rd-ranked Sun, who is competing in just her second main draw of a Grand Slam, from the qualifying tournament to a quarter-final berth at Wimbledon – where the women’s tournament has seen top seed after top seed ousted – came as a surprise.

Here, then, is a starter course.

Sun, 23, was born in Te Anau, a town of 2,538 on New Zealand’s South Island, to a Chinese mother and Croatian father, though her stepfather is German-English and hails from about 320km down the road from Centre Court, where she unseated 2021 US Open champion and British darling Emma Raducanu in the fourth round on Sunday (Monday NZT).

Her family left that small town in New Zealand when she was young for the slightly larger Shanghai, where Sun spent a few years before moving to Geneva.

After all that cultural education, it came time for the trilingual Sun – who speaks bubbly, polished English with nary a hint of an accent, as well as French and Mandarin – to continue her academic education at her mother’s prodding.

Naturally, this citizen of the world chose to attend the University of Texas.

Lulu Sun of New Zealand reacts after winning a point against Lin Zhu of China in the third round on day five at Wimbledon. Photo / Getty Images

“I had no plans on going to university. I thought I was going to go straight to pro. I was still playing juniors... Then I got injured. My mom, she was worried about when am I going to take my exams, all that,” Sun said, yadda yadda-ing her mother as daughters do. “Basically, she saw a message from Howard [Joffe], the coach at Texas. She was like: ‘Oh, my God! This is a good school! You have to go. Text him back.’ I was like, ‘Okay, sure’.”

Sun then proved that particular Longhorn bias had managed to seep into her blood, nestled there next to the Swiss and Chinese and Kiwi and Croatian and German-English influences, despite just one season in Austin, in which she helped the team win an NCAA championship.

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She said she fell in love with the school after comparing it to another Texas institution where she had played a tournament, that institution being Texas Tech.

Lulu Sun of New Zealand during her post-match interview after defeating Emma Raducanu in the fourth round at Wimbledon. Photo / Getty Images

“I was like, ‘Oh, my God, there’s nothing here’,” Sun said, laughing. “I was so in awe with Austin, the city. I loved it so much that I was like, wow, this is a school that’s so big, and they have everything. It was really amazing.”

The grandeur of Austin might feel distant now compared to Sun’s achievements over the past two weeks.

Since Sun fended off a match point that might have bounced her from the second round of qualifying, her feisty, freewheeling game has made her a “first” several times over.

She is the first women’s qualifier to reach the quarter-finals here since Estonia’s Kaia Kanepi in 2010, the first woman from New Zealand to make the Wimbledon quarters and the first Kiwi player to do so since Chris Lewis, the 1983 runner-up to US great John McEnroe.

Lulu Sun of New Zealand plays a backhand to Qinwen Zheng of China in the first round at Wimbledon. Photo / Getty Images

She is perhaps the biggest surprise here, an achievement in itself, given the unexpected nature of the women’s quarter-finalists. The only top 10 seeds remaining are No 4 Elena Rybakina, the 2022 Wimbledon champion, and No 7 Jasmine Paolini, the surprise French Open finalist from last month. Top-seeded Iga Swiatek lost in the third round, No 2 Coco Gauff was upset in the fourth round, and No 3 Aryna Sabalenka withdrew due to a shoulder injury ahead of her first-round match.

Sun will face 28-year-old tour veteran Donna Vekic of Croatia in her quarter-final and will be ready to play the same big-hitting tennis she displayed against Raducanu.

“I don’t think it’s surprising. At the same time, I wasn’t thinking, ‘Oh, I’m going to be in the quarter-finals of Wimbledon,’” Sun said of her run. “I honestly was just like, okay, first match. I got through it. I was like, okay, next match. After I passed quallies, I was super delighted because the last quallies I played at Wimbledon, I lost in the final round of quallies in three sets. I was super disappointed. When you’re so close to qualifying, it kind of hurts your heart. So just getting to the main draw was a big step already. Playing all these players up until now, it’s just opportunity, a new opportunity each time.”

Sun announced herself here with a momentous first-round win over No 8 Qinwen Zheng to notch her first victory over a player ranked inside the top 50. In the fourth round, she won the first Centre Court match of her career against Raducanu, batting away questions about the bias of the British fans by saying they’re not nearly as partisan as those at the French or US Opens.

She watched YouTube videos of Steffi Graf playing Martina Navratilova for inspiration and remembered to come to the net – because the everlasting example of Roger Federer lurks in her mind perhaps stronger than it does for most. Sun played for Federer’s Switzerland until March, at which point she made the difficult decision to represent her nation of birth.

It still feels a bit unnatural for her to have to officially represent a single country at all.

“It was definitely difficult, because I grew up a little bit in New Zealand. I was born there. My family is still there. I grew up in Switzerland as well. Both countries are dear to me,” Sun said. “It wasn’t an easy decision, because it never is when you have to choose between two things... It will always be all the countries that I have been in and have grown up or have a link to; they will always be within me in a way. I don’t think that’s ever going to leave.”