Rafael Nadal, Novak Djokovic and Maria Sharapova shrugged off the Paris gloom to reach the French Open second round as Japanese ninth seed Kei Nishikori became the tournament's first major casualty.
Eight-time champion Nadal, bidding to become the first man to win five Roland Garros titles in a row, beat US wildcard and world number 279 Robby Ginepri 6-0, 6-3, 6-0.
It was Nadal's 60th win at the French Open against just one loss.
World number one Nadal kicked off his campaign yesterday on the secondary Suzanne Lenglen court while title rivals Djokovic and Australian Open champion Stan Wawrinka were handed top billing on the main Philippe Chatrier arena.
It was a decision blasted as "bizarre" by one fellow professional even though Nadal himself had criticised the state of the newly-laid clay on Chatrier after a weekend practice session.
Despite the controversy, it was business as usual for Nadal who fired 27 winners past Ginepri, a semi-finalist at the 2005 US Open whose challenge was undone by 41 unforced errors.
"It doesn't matter where I play," said Nadal who next faces either Paul-Henri Mathieu of France or highly-rated Dominic Thiem of Austria.
"It's always a pleasure and an honour to play at Roland Garros, on Chatrier, Lenglen or any other court. This place has given me unforgettable emotions."
Second seed Djokovic, the 2012 runner-up who is seeking a first Roland Garros title to complete a career Grand Slam, brushed aside Portugal's Joao Sousa, the world 42, in straight sets, 6-1, 6-2, 6-4.
During a match interrupted by rain, the 27-year-old Serb was at his charismatic best, delighting the Philippe Chatrier crowd by sharing a drink with a ballboy as they sheltered beneath an umbrella.
Djokovic, widely regarded as the favourite to dethrone Nadal having beaten the Spaniard in Rome two weeks ago, next faces French hope Jeremy Chardy.
"I played for most of the match quite solid. The end of the match was not so nice from my side because I dropped my serve twice," said Djokovic.
"It was very heavy conditions. The court is not that great, or in a great condition at this moment."
Sharapova, seeded seven and the 2012 champion, needed just over an hour to beat fellow Russian, Ksenia Pervak, the world's 156th-ranked player, 6-1, 6-2.
The 27-year-old, who lost last year's final to Serena Williams, looked comfortable under the cloudy conditions on Chatrier, breaking her opponent five times.
Sharapova will next face Bulgaria's 2010 Wimbledon semi-finalist Tsvetana Pironkova.
"First matches at Grand Slams are always tough, no matter how prepared you are, no matter how many matches you've played," said Sharapova, now 13-1 on clay in 2014 with titles in Stuttgart and Madrid.
"There is always a bit more tension in that type of Grand Slam atmosphere. It's certainly more special, especially when you walk out on court."
Nishikori miserable -
Nishikori was left feeling as miserable as the Paris weather, clearly still suffering from his recent back injury.
Nishikori, 24, and coached by 1989 champion Michael Chang, was the first Japanese man in 75 years to make the fourth round in Paris in 2013.
But on Monday, there was never any sign that he would repeat that feat as he went down 7-6 (7/4), 6-1, 6-2 to Slovakia's Martin Klizan.
Nishikori won the Barcelona claycourt title last month but then had to quit the Madrid Masters final against Nadal with a back injury that also forced him out of the Rome Masters.
The world number 10 looked distinctly half-fit on Court 1 where he was broken 10 times, hit 10 double faults and committed 40 unforced errors
Left-handed Klizan, 24, one of six former junior champions in the main draw, goes on to face Robin Haase of the Netherlands."It sucks," said Nishikori.
After rain delayed the start of yesterday's programme by more than an hour, play was halted again barely two hours later at 1230GMT for a further hour and a quarter.
Seven matches on the schedule were cancelled until today.
But there was still time for Dominika Cibulkova, the Slovak ninth seed, to beat France's Virginie Razzano 7-5, 6-0 and Italian 12th seed Flavia Pennetta to see off Austria's Patricia Mayr 6-2, 6-2.
German 16th seed Sabine Lisicki, last year's Wimbledon runner-up and who is coached by former world number one Martina Hingis, defeated French wildcard Fiona Ferro 6-1, 7-5.
Also going through was Austria's Tamira Paszek whose 6-2, 7-6 (7/5) win over Belgium's Alison van Uytvanck was her first at Roland Garros for seven years.
Italy's 17th seed Roberta Vinci slipped up, however, losing to France's Pauline Parmentier 3-6, 6-3, 6-2.