France's top player Jo-Wilfried Tsonga began his bid for French Open glory on Sunday with a four-set win - but Andy Roddick fell at the first hurdle.
Tsonga progressed to round two at Roland Garros but not before a first-set scare against the little-known Andrey Kuznetsov.
Using go-for-broke tactics, the Russian qualifier made a storming start, cracking 17 winners in the first set to break Tsonga twice. He also managed to save eight break points as he took the set 6-1.
The scoreline did not reflect the closeness of the contest and Tsonga soon hit back. Kuznetsov began to hit more unforced errors than winners and the fifth seed's class began to tell.
After levelling the match at one set all, he took control to record a 1-6 6-3 6-2 6-4 victory on Court Philippe Chatrier.
Tsonga admitted he was worried by Kuznetsov's start but realised the world number 160 could not keep it up.
"At the beginning I thought, OK, I need to put more intensity on my first serve or on the first two shots in the rallies,'' he said.
"And it worked OK. But by doing that he started scoring quite a few points. Against such a player, you feel let's wait for the storm to be over and in half an hour I'll see what's going on.''
There was also joy for France's Nicolas Mahut, who took out former US Open champion Roddick.
Mahut, who out-aced his big-serving opponent, triumphed 6-3 6-3 4-6 6-2 as Roddick's claycourt woes returned.
The Frenchman, ranked 88 in the world and most famous for his record-breaking marathon match with John Isner at Wimbledon, edged two tight opening sets.
Roddick hit back to gain the break at the right time and take the third but with Mahut superior on serve and with his groundstrokes, there was an air of inevitability in the fourth.
All in all, Roddick was broken seven times - surrendering his famous serve in the last game as he slumped out in disappointing style.
Roddick, who recently spent two months on the sidelines with a hip injury, said: "I lost a match to a guy who played better than I did. I made a choice. I played. I'm fine. I lost.
"I move just horrendously out here. My first step is just so bad on this stuff. I feel like I'm always shuffling or hopping or not stopping or something. So my footwork on this stuff now is just really bad."
Earlier, Argentine Juan Martin del Potro had to survive an injury scare and sweltering 30-degree heat to book his place in the second round.
He eventually prevailed 6-2 6-7 6-2 6-1 against Spain's Albert Montanes.
The ninth-seeded Del Potro, a Roland Garros semi-finalist in 2009, received lenghty treatment on a sore left knee at the end of the second set before motoring through to prevail with a service winner on his first match point in a shade over three hours.
The 2009 US Open champion started brightly, sprinkling the court with forehand winners to open a 6-2 4-2 lead before seizing up as claycourt specialist Montanes fought back to take the second-set tie-break 7-5.
Del Potro, however, regrouped after the trainer strapped his left knee to set up a second-round meeting with home favourite Edouard Roger-Vasselin.
The 23-year-old, the only man outside of Novak Djokovic, Rafael Nadal and Federer to win a Grand Slam title in the last seven years admitted afterwards that the soaring temperatures were taking their toll.
"I was struggling a little, but I had some good treatment which allowed me to finish the match," said Del Potro.
"Roland Garros is a physically-demanding tournament. I have to keep that in mind as I am playing well at the moment."
Also making the last 64 on the opening day of the 2012 tournament was 2003 winner Juan Carlos Ferrero, who defeated French wildcard Jonathan Dasnieres de Veigy 6-1 6-4 6-3.
Ferrero, playing in his 12th Roland Garros, next meets Croatian 21st seed Marin Cilic, who defeated Spain's Daniel Munoz 6-4 6-4 7-5.
Stanislas Wawrinka also progressed after surviving a scare against Italy's Flavio Cipolla.
The Swiss number two, seeded 18th, looked to be in control when he won the opening two sets against unheralded Italian Flavio Cipolla, but contrived to lose the next two and the match went into a decider.
Wawrinka roared into a 3-0 lead, though, and went on to complete a torturous 6-3 6-3 4-6 3-6 6-2 win.
Fernando Verdasco also progressed to the next round thanks to a comfortable straight-sets victory against Belgian Steve Darcis.
The Spanish 14th seed came through 6-3 6-2 7-6 (7-4).
However, one seed to fall was number 30 Jurgen Melzer. The 2010 semi-finalist was beaten in five sets by Germany's Michael Berrer.