Andy Roddick's French Open hopes were ground into the Roland Garros clay on Thursday by a tenacious Argentine who never lost belief.
With the second seed's demise, American chances of a men's champion at the second Grand Slam of the year also disappeared.
Journeyman Jose Acasuso won 3-6, 4-6, 6-4, 6-3, 8-6 in three hours 21 minutes, propelling him into the third round of a grand slam for the first time and leaving Roddick a second-round loser in Paris for the second year in a row.
"I hate it... I mean, it's terrible," the former world number one said. "I mean, that pretty much sums it up... I want to do well here so badly.
"I'll tell you, it's an extremely long flight home. After this, you just kind of want to regroup and then you can't wait to get out there and try to right a wrong again.
"The only thing I can do is keep working hard... just do my best to turn it around."
Acasuso was ecstatic. "I'm so happy to have won... it shows me even if I am losing a match I can still win it," he said.
In the women's singles, Maria Sharapova remained ice-cool under a blistering sun to repel the free hitting of French wild card Aravane Rezai and reach the third round.
After a shaky first round in which she was stretched to three sets by fellow Russian Evgenia Linetskaya, the second seed upped her game to beat fellow 18-year-old Rezai 6-3, 6-2 on centre court.
Sharapova dismissed concerns over her claycourt form with an assured performance against a gutsy opponent buoyed by her home fans.
SIMPLE PLAN
Rezai, ranked 242 places behind the world number two, had a simple game plan of pelting the ball as hard as she could and going for winners.
It served her well in the opening exchanges as she streaked into a 3-1 lead but Wimbledon champion Sharapova kept her cool to reel in the Frenchwoman.
"She had nothing to lose and she was just going for her shots," Sharapova said. "Some balls were just too good.
"But I finally started feeling a good rhythm out there and began playing better."
Rezai was a little less gracious in defeat when asked if she had found the Wimbledon champion impressive.
"Well, not especially," she said. "There's a lot of media around her, but she's a player among other
Third seed Amelie Mauresmo and Moscow-born Frenchwoman Tatiana Golovin soon restored home pride, however.
Seventeenth seed Golovin thrashed Italy's Antonella Serra Zanetti 6-0, 6-1 and Mauresmo pummelled young compatriot Alize Cornet 6-0, 6-2.
The 15-year-old Cornet, who grew up admiring Mauresmo, said: "I was not overawed by the court nor by the people but I was definitely overawed by Amelie."
Mauresmo eased up on her admirer towards the end, allowing her to win two games in the second set.
"It reminded me of the first time I stepped into a big court," she smiled. "I thought she was great. She just went for it. She's got a great future."
Belgian former world number one Justine Henin-Hardenne refused to let a sore back sidetrack her as she beat Spain's Virginia Ruano Pascual 6-1, 6-4.
RELIEVED CORIA
The 2003 champion made her comeback to the tour two months ago after spending six months out recovering from a viral illness.
Although she has emerged as one of the French Open favourites after winning three successive titles, concerns about her fitness were again raised when the 10th seed called the trainer for her back when leading 5-0 in the first set.
"I've had an injury in my back for a few weeks, so it's something I'm having to deal with," said the Belgian who next faces Spain's Anabel Medina Garrigues.
"It is a slight sprain...because it's close to a nerve, it's painful. Probably not now, but I will (eventually) have to take a little rest."
Men's third seed Marat Safin refused to bow to a painful knee and thundered into the third round with a 6-7, 6-3, 7-5, 6-1 win over Czech Lukas Dlouhy.
"My knee still hurts as I have tendonitis," he said. "It starts to bother me each time more and more. So I have to take care of it.
"It's hurting me. If I call the doctor it's not because I have nothing better to do."
The Australian Open champion next faces fellow former world number one Juan Carlos Ferrero after the Spaniard beat Czech Jan Hernych 6-4, 6-4, 6-2.
Guillermo Coria advanced after his Serbian opponent Novak Djokovic retired with respiratory problems. Argentine Coria, runner-up to compatriot Gaston Gaudio last year, was leading 4-6, 6-2, 3-2 when Djokovic quit.