Rafa Nadal suffered a severe fright before punching the air with both fists in joy as he began his French Open defense on Tuesday with a dogged win over John Isner, while fit-again Kim Clijsters sauntered through her first match.
World number one Nadal was forced into his first five-set match at Roland Garros and risked becoming the first men's champion to go out in the first round on the Paris clay before finally outlasting the giant American 6-4 6-7 6-7 6-2 6-4.
"It's always a very, very close match with John," Nadal said in a courtside interview. "I was there, I fought all the time. In the tiebreaks I was probably too nervous."
British fourth seed Andy Murray was broken twice in a 6-4 6-1 6-3 victory over Eric Prodon, a 29-year-old local qualifier who has won only one match on the main tour and was making just his fourth grand slam appearance.
Women's second seed Clijsters had not played for almost two months after injuries, including an ankle problem that she picked up at her cousin's wedding.
Despite wearing strapping on the ankle, the Belgian easily outfought Anastasia Yakimova of Belarus 6-2 6-3 to prove her fitness and lay down a marker in a women's draw largely devoid of grand slam title experience.
China's Li Na, who lost to Clijsters in January's Australian Open, started with an uninspiring 6-3 6-7 6-3 win over Barbora Zahlavova Strycova as the day began with cloud.
The sunshine came as in-form Maria Sharapova routed Mirjana Lucic 6-3 6-0 in a yellow dress and while Ana Ivanovic rivaled the Russian in the fashion stakes with a pink number, the tearful ex-champion lost 7-6 0-6 6-2 to Sweden's Johanna Larsson.
Queues at the entrances to the famous courts in western Paris lengthened as temperatures warmed up and anticipation rose for Nadal's first match.
The Spaniard is seeking a sixth title in seven years but Australian Open champion Novak Djokovic, who easily won his first match on Monday, is threatening to break his dominance after a stunning unbeaten start to the year.
American Isner is best known for his 11-hour epic match against Nicolas Mahut at Wimbledon last year and he made Nadal sweat profusely with his high-bouncing serve and surprising deftness at the net.
He dominated the two tiebreaks, winning 7-2 in both as Nadal struggled to cope with Isner's all-round game.
Yet, using an inner-strength he has shown so often on other surfaces, "King of clay" Nadal dug deep to break twice, take the fourth set and steal most of the momentum.
Isner lost his way in the final set, dropping serve in the third game as Nadal closed out a testing tussle to set up a second-round meeting with compatriot Pablo Andujar.
Eighth seed Jurgen Melzer of Austria had no such difficulty seeing off German Andreas Beck 6-3 6-4 6-2 and Fernando Verdasco battled past Juan Monaco 6-2 7-5 4-6 6-4 before home hope Gilles Simon beat Michael Russell 6-3 4-6 6-1 6-0.
Murray did not need to produce his best against the slightly rotund Prodon, who broke in the first set with a drop shot.
The Scot, who next plays Italian Simone Bolelli, found more rhythm in the second but was broken again in the third set as Prodon's remarkably laidback but occasionally successful volleys and smashes amused the fans.
There were more laughs when organizers announced that American Ryan Harrison, who threw his racket into a tree when losing in qualifying last week, had won a lucky loser berth but he lost 6-1 6-7 6-3 7-5 to 2010 runner-up Robin Soderling.
The feelings on Court Philippe Chatrier were completely different as France's Virginie Razzano, whose coach and fiance died eight days ago from a brain tumor, lost her match to Australian Jarmila Gajdosova 6-3 6-1 to heartfelt applause.
"I had a lot of emotion and pain," Razzano said.