Greg Rusedski failed in his bid to win his first match at the French Open for four years when he lost to Flavio Saretta in straight sets.
The Briton managed to cancel out an early break of serve by the Brazilian at 2-2, but struggled from then on.
Qualifer Saretta swept through the first set and saved two Rusedski set points in the second-set tie-break.
Rusedski's resistance was well and truly broken, with Saretta eventually coming through 6-2 7-6 (9-7) 6-3.
"I must give credit to Saretta, he played really well," said the British number two.
"I am disappointed because I was training well and my serve also was good during training.
"But I guess I could have got into the match better with a more efficient serve."
"This is a question of confidence, the more matches you play the better your confidence gets," said Rusedski, who had only six aces and nine double faults.