Reigning US Open champion Emma Raducanu had to battle hard in her Roland Garros main-draw debut on Monday before the No.12 seed from Great Britain outlasted Czech qualifier Linda Noskova 6-7(4), 7-5, 6-1.

In a battle between two of the nine teenagers in this year’s main draw, 19-year-old Raducanu pulled off a 2-hour and 37-minute comeback against 17-year-old Noskova, who won the Junior Roland Garros singles title last year.

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"Noskova, she's pretty young, but she's definitely powerful," Raducanu said afterward. "She hits the ball extremely hard. I was finding as soon as I was dropping my ball short she was all over me.

"I just thought, 'You know, you've got to go out doing something.' So I started hitting the ball much better, I think, and keeping her off-balance. She was definitely hitting some great shots. Even on the run on her backhand wide she was hitting the line so well. But I think I just found a better way."

Youth movement: Noskova, who was playing her first tour-level main-draw match, was the youngest player to make the 128-player field in Paris this year.

By winning the first three Grand Slam qualifying matches of her career last week, Noskova became the youngest player to come through Roland Garros qualifying since Michelle Larcher de Brito did so at age 16 in 2009.

But Raducanu took the victory, in the midst of her first year playing tour-level matches on clay. Raducanu's first tour-level match on the surface came earlier this season at Billie Jean King Cup qualifying, before going 4-3 at Hologic WTA Tour events in Stuttgart, Madrid and Rome.

Raducanu prevented Noskova from becoming the first qualifier to upset a Top 12 seed at a major since Raducanu did it herself, when she knocked out No.11 Belinda Bencic during her stunning title run at last year’s US Open.

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Match moments: Noskova found powerful winners from both wings to take the first set in over an hour. After firing a backhand winner down the line to break Raducanu at love for a 4-3 lead in the second set, the qualifier was on the precipice of her first win over a Top 100 player.

But Raducanu swiftly broke back for 4-4, and the Brit made her move at 6-5 when she converted her fourth set point in that game with a deft drop shot. After turning the momentum in her favor, Raducanu breezed through the third set to reach the second round in her Paris debut.

Raducanu will now meet Aliaksandra Sasnovich in the second round. Sasnovich already has an upset win over Raducanu, which came at Indian Wells last year.

Tomljanovic takes out Kontaveit

While Raducanu avoided the upset, the same couldn't be said for No.5 seed Anett Kontaveit. The Estonian became the fourth Top 10 player to fall in Round 1 over the first two days in Paris, and second on Monday after defending champion Barbora Krejcikova, when she fell to Australia's Ajla Tomljanovic, 7-6(5), 7-5.

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Tomljanovic held on for her fifth career Top 10 win in 1 hour, 52 minutes despite letting a 3-0 lead slip in the first set, and a 4-2 lead in the second. She also saved a set point in the second set serving in the 10th game.

Eight years ago, Tomljanovic scored her first career Top 10 win at Roland Garros by beating then-No. 3 Agnieszka Radwanska in the third round, and her win over Kontaveit snapped a six-match losing streak for her against the Top 10 on clay.

"These are the matches that I love to get up for," Tomljanovic said. "I think in my career I played a lot of top players first rounds in Slams and I always feel like I can win, but it never really matters until you really do it.

"I think this mostly does a lot for my confidence. When you really come out with a win, it's different than just putting up a good match. So that makes me happy."