Zheng Qinwen defeated the highest-ranked opponent of her career Thursday in the second round of Roland Garros. The Chinese teenager came back from a set and a break down to upset 2018 champion Simona Halep 2-6, 6-2, 6-1.

Zheng, 19, needed just under 2 hours to pull off the win and reach the third round of a major for the first time. Zheng is playing only the second Grand Slam event of her career, following this year’s Australian Open.

A big imagination and a bigger game: Inside the rise of Zheng Qinwen

"I feel really nice," Zheng said afterward. "It's a second Grand Slam for me, so I enjoy every chance that I stand on court. I try to give my best like always and I'm glad [about] my performance today."

Breakthrough victory: The World No.74 Zheng had previously gone 0-3 against Top 20 players in her career, including a straight-sets loss to Halep in the Melbourne Summer Set 1 semifinals in January. 

Zheng struck 27 winners Thursday, three times Halep's total.

"In [their Melbourne match] I learned a lot, that she was a very consistent player, and in that moment I [didn't] have too much patience on court," Zheng said. "This time I tried to stay with her more on court, trying to be more patient, find the chance to win the rally, and that's what I learned. So I'm glad that I can perform on court today, and that's how I got the win."

Signs were already present that Zheng’s powerful game was in sturdy form. In her opening-round match, Zheng fired 28 winners, including six aces, to beat Maryna Zanevska in two quick sets.

Halep had already struggled against a teenager in her first round, where she was pushed to three sets by 18-year-old lucky loser Nastasja Schunk.

Match moments: Halep started off strong on Court Simonne Mathieu on Thursday, easing through the first set with only four unforced errors. A break for a 2-1 lead in the second set, helped by a Zheng double fault on break point, gave Halep the advantage.

But the match turned thereafter, where Zheng found down-the-line winners and a stellar pass to break back immediately after a 10-minute game. Zheng’s aggressive game kicked into play from there, and she reeled off five games in a row to take the second set.

A pair of visits from the physio did not help Halep stem the tide in the decider, and Zheng cruised through the final set, where she went 13-for-13 on her first-service points.

"It's just a tennis match, so I have to see it a little bit more relaxed," Halep said. "Probably put pressure on myself too much, because I really wanted to do well. I felt good. I practice. I work hard. But just didn't happen, and probably I got a little bit of panic during that thinking, overthinking."

Cornet knocks out Ostapenko

Zheng will face a home favorite next, when she takes on French No.1 Alizé Cornet in the third round. It will be there first meeting. Cornet outlasted No.13 seed and 2017 Roland Garros champion Jelena Ostapenko 6-0, 1-6, 6-3 in the night match on Court Philippe Chatrier.

After splitting two lopsided sets, Cornet took charge in the third set by fending off four break points before holding for 2-0. Cornet pulled through close games mid-set by extending rallies to their limits, drawing miscues from hard-hitting Ostapenko.

Cornet's gritty hold for 5-3 was followed by a quick break, giving the Frenchwoman the victory in front of boisterous home support.

Cornet, who defeated Halep to make her first Grand Slam quarterfinal at this year's Australian Open, is making her 61st consecutive Grand Slam main-draw appearance. She is one behind Ai Sugiyama’s Open Era record of 62 straight majors.