Paris: Former champion Stan Wawrinka brushed aside Andy Murray 6-1, 6-3, 6-2 in the marquee match-up on the opening day of Roland Garros on Sunday.
Wawrinka, the 16th seed who took the title in 2015, had also come out on top when the two last met in Paris in a five-set semi-final in 2017.
Murray, who needed a wild card to play in Paris this year, was competing in a clay court tournament for the first time since that clash.
Wawrinka fired 42 winners past the former world number one and will take on Dominik Koepfer of Germany for a place in the last 32.
Top-seeded Simona Halep won 10 straight games in beating Sara Sorribes Tormo 6-4, 6-0 to reach the second round extend her winning streak to 15 matches.
Meanwhile, Venus Williams suffered a third successive first round exit at the French Open as she lost in straight sets to Slovakia's Anna Karolina Schmiedlova.
Wearing thick black leggings and a long-sleeved pink jersey to combat the chilly conditions on Court Philippe Chatrier, Halep made a series of unforced errors and trailed 4-2.
But then she found her range, clinching the first set with a hold to love and sealing victory on her first match point when her Spanish opponent clipped a forehand wide.
She is ranked second but seeded first at Roland Garros because defending champion Ash Barty skipped coming to Paris because of coronavirus concerns. Halep won titles on clay in in Prague and Rome and her winning run " interrupted by the pandemic " dates to February.
She next faces either countrywoman Irina Camelia Begu or Jil Teichmann of Switzerland.
Halep was not alone in wrapping up warm in the cold.
Over on Court Suzanne Lenglen, US Open runner-up Victoria Azarenka experienced a vastly different temperature to Flushing Meadows only two weeks ago.
The tenth-seeded Azarenka fumed when match officials didn't immediately send her and opponent Danka Kovinic back to the locker-room during a rain interruption.
"I am going to get frozen," she complained. "No. I'm not waiting here a couple of minutes because I'm cold. It's eight degrees, eight degrees, I live in Florida, I am used to hot weather."
Before walking off court, Azarenka grumbled "it's ridiculous. It's too cold ... What's the point? Sitting here like ducks."
Still, she made short work of her match, beating Kovinic 6-1, 6-2. She next faces either Venus Williams or Anna Karolina Schmiedlova, who were playing their match later Sunday.
Coronavirus restrictions mean only 1,000 people are allowed per day at the tournament in western Paris.
But only 150 were there to see 11th-seeded David Goffin begin his match against Next Gen ATP Finals champion Jannik Sinner at just after 11 a.m. under the new Chatrier roof.
Goffin, a former quarterfinalist here, was the first seeded player to be knocked out when he lost 7-5, 6-0, 6-3.
His countrywoman Elise Mertens " the 16th seed " fared better in beating 122-ranked Russian Margarita Gasparyan 6-2, 6-3.
The 40-year-old Venus, runner-up at Roland Garros to sister Serena in 2002, was beaten 6-4, 6-4 by an opponent who snapped a 12-match Grand Slam losing streak.
It marked Williams' third first round defeat in a row at a Slam after exiting the US Open and Australian Open at the same stage.
The seven-time Grand Slam champion has not been past the third round at a major since 2017. She has lost eight of nine matches on tour this year.
Williams dropped serve six times in cold, blustery conditions in Paris as Schmiedlova registered her first main draw victory at a Slam since the 2015 US Open.
Her reward is a second round tie against two-time Australian Open winner Victoria Azarenka.
Sebastian Korda, the son of 1992 Roland Garros runner-up and 1998 Australian Open champion Petr Korda, defeated Andreas Seppi in the first round.
The 20-year-old Korda came through qualifying to earn a place in the Roland Garros main draw for the first time, and overcame the veteran Seppi 6-2, 4-6, 6-3, 6-3 in gloomy conditions.
He credited his father for his lasting support after notching his first victory at tour level.
"My dad is a really big help, he oversees everything," said Korda.
"He doesn't really travel with me that much, but we're always in contact and whenever I'm home we're always on the court together.
"He's a really big help and I don't think I would be anywhere near where I am right now without him."