Iga Swiatek and Carlos Alcaraz got the Paris Olympics tennis competition started with first-round victories Saturday under closed roofs at Roland Garros, the site of their French Open titles less than two months ago.

Novak Djokovic also won in straight sets as he, like Swiatek and Alcaraz, opened a bid for a first Olympic gold medal. Djokovic's second-round opponent could be longtime rival Rafael Nadal, who was scheduled to play his opening singles match Sunday.

Nadal, the Spaniard who won a record 14 of his 22 Grand Slam titles at the French Open and owns two Summer Games golds, was a surprise torch carrier during the rain-soaked opening ceremony along the Seine River on Friday night and was slated to compete alongside Alcaraz in doubles on Saturday night.

The No. 1-ranked Swiatek claimed four of her five career major championships in Paris and grabbed the last four games to beat Romania's Irina-Camelia Begu 6-2, 7-5, while reigning French Open and Wimbledon champ Alcaraz defeated Lebanon's Hady Habib 6-3, 6-1.

Serbia's Djokovic, who is seeded No. 1 in the men's field after Jannik Sinner pulled out with tonsillitis, needed less than an hour to dismiss Australia's Matthew Ebden — a doubles player participating in a tour-level singles match for the first time in two years. Ebden got into the singles bracket because he was in Paris to play doubles and thus available when 16th-ranked Holger Rune of Denmark withdrew with an injured wrist.

Ebden's lone game came after he was already down 6-0, 4-0 — and he celebrated by pulling the front of his yellow shirt over his head and baring his chest to roars from the flag-dotted crowd.

Poland's Swiatek, who won a third consecutive championship at Court Philippe Chatrier just seven weeks ago, got broken in that same stadium to trail 5-3 in the second set before getting back to her usual clay-court expertise. She wrapped up the victory by breaking at love when Begu double-faulted on the last point.

Day 1 of tennis began with showers that might have contributed to slow lines for umbrella-toting spectators at the facility's security checks near entrances. All of the matches on the 10 courts without retractable roofs were ultimately cancelled for the day.

It's a good thing the French tennis federation built a pair of movable covers recently: 15,000-capacity Chatrier added one in 2020, and the second-largest arena, 10,000-capacity Court Suzanne Lenglen, has one as of this year.

Italy's Jasmine Paolini, who was the runner-up to Swiatek at the French Open in June and to Barbora Krejcikova at Wimbledon two weeks ago, was the first tennis player to win a match at these Summer Games, eliminating Romania's Ana Bogdan 7-5, 6-3 at Lenglen.

Canada's tennis stars were among the players affected by the cancellations.

Laval, Que., native Leylah Fernandez, the 16th seed, was scheduled to play Czech player "Karolina Muchova, a 2023 French Open finalist, on Saturday. Muchova, ranked 29th in the world, won their only previous encounter in 2022 on hard courts in Miami.

Bianca Andreescu, of Mississauga, Ont., was set to face Denmark's Clara Tauson in her opening match.

Montreal's Felix Auger-Aliassime, the 13th seed, was also set to start his campaign against American Marcos Giron, ranked 38th.

Fernandez and Ottawa's Gabriela Dabrowski also saw their match cancelled in women's doubles. The Canadians, seeded fifth, were slated to play France's Clara Burel and Varvara Gracheva.

The Canadian singles matches were rescheduled to Sunday along with Fernandez and Dabrowski's doubles match. Auger-Aliassime and Milos Raonic of Thornhill, Ont., will start their men's doubles tournament later this week. The same goes for mixed doubles, where Auger-Aliassime will play with Dabrowski.

Nadal and Alcaraz — Spain's old-and-new pairing of tennis superstars — won the first match they've ever played together as a doubles team, eliminating Argentina's Maximo Gonzalez and Andres Molteni 7-6 (4), 6-4.

The 38-year-old Nadal has not made clear whether the Summer Games will be the last event of his storied career, although there's been plenty of speculation it will be, given all of his recent injury issues — he wore white tape wrapped around his right thigh Saturday — and his connection to Roland Garros. That's the clay-court facility being used for these Olympics and the site of the annual French Open, where he claimed a record 14 of his 22 Grand Slam titles.

While he has played only sparingly over the past two seasons because of hip surgery and an abdominal muscle problem, and lost in the first round of this year's French Open to eventual runner-up Alexander Zverev, Nadal looked just fine Saturday. Then again, doubles requires far less movement and stamina than singles, of course.

Nadal's movement appeared OK, and he showed off his tremendous volleying ability, including one back-to-the-net, over-the-shoulder, no-look winner in the first set. After the point, he wheeled and punched the air. Fans celebrated wildly.

Nadal frequently slapped palms with Alcaraz between points — whether won or lost — and occasionally patted his much-younger partner on the shoulder during pauses in the action.

When the match ended with a volley off Alcaraz's racket, Nadal raised both fists. Alcaraz turned to his new partner and yelled, "Vamos!"

Among the other big names from the sport scheduled to play later Saturday was four-time major champion Naomi Osaka.

Coco Gauff, the female flag bearer for the United States on Friday, was slated to make her Olympic debut Saturday with Jessica Pegula in doubles. Gauff won the French Open doubles title with Katerina Siniakova of the Czech Republic last month and the U.S. Open singles trophy last September.

Three years ago, Gauff missed the Tokyo Games after testing positive for COVID-19 right before she was supposed to fly to Japan.

Angelique Kerber eliminated Naomi Osaka 7-5, 6-3 in the first round of the Paris Olympics tennis competition on Saturday night in a matchup between former No. 1-ranked players who own multiple Grand Slam titles.

Kerber has said she will retire after competing for Germany at these Summer Games.

Osaka was hoping for a better showing than she had at the Tokyo Olympics three years ago in her native Japan. She was supposed to be one of the big stars and received the honor of lighting the cauldron at the opening ceremony.

But Osaka lost in the third round there and said she felt a real sense of pressure to perform well in front of her home fans. She was born in Japan to a Japanese mother and Haitian father, and the family moved to the United States when Osaka was 3.