In the final round of qualifying at Australian Open 2016, Maria Sakkari edged past Zhu Lin in straight sets to secure her main draw debut.
Seven years later, the Chinese right-hander avenged that loss with the biggest win of her career: a stunning 7-6(3) 1-6 6-4 upset over the Greek sixth seed.
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"Am I in a dream?" said a thrilled, tearful Zhu in her on-court interview. "No words can describe how I feel right now."
"I'm so happy," continued the ecstatic world No.87 Zhu, acknowledging that the two hour and 33 minute battle to secure her maiden Grand Slam fourth round berth was both mentally and physically tough.
"She's a fighter," said Zhu, who landed just 29 winners to Sakkari's 42. "She never gave up ever…she's got [a] reason to be a top 10."
"Today I just keep pushing, keep being aggressive and play my tennis and keep believing in myself," added Zhu, who won just two more overall points than her foe in the close encounter.
"I tell myself [to] be relaxed, enjoy the stadium, enjoy the crowd," she said, grateful for the appreciative fans on Margaret Court Arena.
Zhu is the first Chinese player to reach the fourth round at Melbourne Park and to take out a top-10 seed - since Qiang Wang shocked Serena Williams in 2020.
She pointed out her monumental victory arrived on the eve of the Lunar New Year.
"Chinese New Year, it means a lot to us," she said.
Zhu joins countrywomen Li Na, Zheng Jie, Peng Shuai, Zhang Shuai and Qiang as the only six players from their nation to reach the round of 16 at the year's first major.
Having never won a set against a top-10 player in six attempts, Zhu adds that her victory over Sakkari gives her belief that she can play at this new level.
"It took me a long way to get here," she explained. "And so that's why I'm so emotional tonight."
Her win over Sakkari came days after she surprised 32nd seed Jil Teichmann to clinch her first victory over a seed at a major.
A breakthrough has been years in the making. Introduced to tennis at the age of four by her father, Zhu began the arduous pursuit of amassing professional ranking points in 2009.
Career-altering wins have been hard to come by, and her top-20 conquests comprise a literal shortlist of Petra Kvitova, in 2017, and Elise Mertens, in 2019.
"There [were] a lot up and downs…sometimes I think about maybe I'm not good enough for tennis, I think about retire[ment]," she admitted.
"But my family, my friends, they always talk to me. They believe I can be a better player, so they push me every day."
"I wouldn't be here without you guys," she said earlier, profusely thanking her team on court.
Armed with unwavering support from those closest to her, the Beijing resident strung together a solid 2022 season with wins over players including Alize Cornet and Katerina Siniakova to reach a career-high No.58 in October.
She revealed that a 6-1 6-2 loss that month at the Guadalajara Open to Roland Garros semifinalist Daria Kasatkina was somewhat of a lightbulb moment.
"After that match I start[ed] to believe in myself…that's so important in tennis. Sometimes [it] just click[s] and change[s] everything," said Zhu, who reached the quarterfinals at the ASB Classic in Auckland earlier this month with victories over Madison Brengle and seven-time Grand Slam champion Venus Williams.
In the fourth round, Zhu has a first-time duel with two-time AO champion Victoria Azarenka, the world no.24 who dispatched Madison Keys on Friday.
"It's going to be a very tough match for me," Zhu said. "I['ll] just keep playing like I played today and trust myself, enjoy the match. Who knows?" she laughed.