Italy's Jannik Sinner plays a shot against Belgium's David Goffin (not in frame) in the first round match of the French Open tennis tournament at the Roland Garros stadium in Paris, France, Sept 27, 2020. (CHRISTOPHE ENA / AP)

PARIS - Italian teenager Jannick Sinner made his Roland Garros debut with an impressive 7-5, 6-0, 6-3 win over 11th seed David Goffin on Sunday, while women's top seed Simona Halep celebrated her 29th birthday with a straight-set victory over Spaniard Sara Sorribes Tormo.

Italian teenager Jannick Sinner ripped 11 games in a row to defeat David Goffin of Belgium for the second time in as many head-to-head meetings

The match between Sinner and Goffin was the first match under the new roof on Court Philippe-Chatrier, as the first day of this year's French Open turned out to be a stormy one.

"The conditions are not easy. It's quite slow. The roof, obviously it helps a lot. especially in the next week, you never know if it's raining or not," said the Sinner.

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The Italian rising star ripped 11 games in a row to defeat the Belgian for the second time in as many head-to-head meetings.

"At the beginning, it's never easy, especially at the beginning of a new tournament. It's the first time for me here at Roland-Garros," the 19-year-old said.

"It's obviously an honor to play at the center court, playing against David, he is a great player. I know him very well, we're good friends, so it's not easy."

Germany's Alexander Zverev gestures after playing a shot against Austria's Dennis Novak (not in frame) in the first round match of the French Open tennis tournament at the Roland Garros stadium in Paris, France, Sept 27, 2020. (CHRISTOPHE ENA / AP)

Zverev overcomes slow start

In another game, US Open runner-up Alexander Zverev overcame a slow start to launch his French Open challenge with a 7-5 6-2 6-4 victory over Austrian Dennis Novak.

Zverev, who had not played on clay since last year, trailed 4-1 in the opening set before he turned the screw on Court Philippe Chatrier, whose roof remained open despite a light drizzle.

“I didn’t play any claycourt before this, it’s my first one (this year) and it was not easy. It was rainy and cold, I needed to get used to it, said the 23-year-old Zverev.

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Romania's Simona Halep celebrates after defeating Spain's Sara Sorribes Tormo in two sets in the first round match of the French Open tennis tournament at the Roland Garros stadium in Paris, France, Sept 27, 2020. (CHRISTOPHE ENA / AP)

Halep cruises past Tormo

Former world No. 1 Halep, who has just clinched the title in Rome earlier this week, cruised past Tormo 6-4, 6-0 to advance, at the same time extended his winning streak to 15 matches in a row.

"I'm really pleased with the victory. It's always tough to start the tournament. I was a bit nervous. She played really well in the first set, she didn't miss. Then I just found the rhythm," said the 2018 champion.

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Venus Williams of the US plays a shot against Slovakia's Anna Karolina Schmiedlova (not in frame) in the first round match of the French Open tennis tournament at the Roland Garros stadium in Paris, France, Sept 27, 2020. (MICHEL EULER / AP)

Venus Williams slumps to opening defeat

Former French Open runner-up Venus Williams suffered her second successive first-round loss in a Grand Slam as she went down 6-4 6-4 to Slovakia’s Anna Karolina Schmiedlova on Sunday.

With a chill wind blowing and drizzle falling on the Simonne-Mathieu arena, the 40-year-old Williams began strongly but got bogged down in a baseline battle on a slow surface.

The American has now fallen in the opening round at the French Open for the past three years.

As required by the government, the maximum limit of attendees per day at this year's French Open has shrunk to only 1,000 in response to the resurgence of the COVID-19 pandemic in and around Paris.