Paris ? His back rigid, his feet shuffling in stutter steps, his face contorted from a burning pain down his leg, Andre Agassi arrived at a crisis in his career.

His future in tennis hinges not so much on his age, 35, as on the inflamed sciatic nerve that flared up and rendered him helpless in the middle of his first-round match at the French Open. It’s the kind of chronic injury that has sent other champions into retirement, and it could ultimately do that to Agassi, even if he’s not quite ready to walk away.

He’s fought that pain for months, sought relief from it with cortisone, but felt it come back with a vengeance Tuesday when it radiated from his lower back to his right hip and down to his ankle. Groundstrokes hurt. Serves hurt more. Agassi considered quitting the match even when he led two sets to one, but he grimaced and played to the end, falling in five sets to No. 95-ranked qualifier Jarkko Nieminen.

Andre Agassi returns a shot during the first round of the French Open. Agassi fell to Jarkko Nieminen, 7-5, 4-6, 6-7 (6), 6-1, 6-0, Tuesday in Paris.

“It was getting worse by the minute,” Agassi said of the pain that struck him in the third set of his 7-5, 4-6, 6-7 (6), 6-1, 6-0 loss. “I knew it wasn’t going to be pretty after that. But I didn’t want to walk off. I just didn’t want to do it. And there’s nothing the trainer could do.

“I almost shook hands at two sets to one up because to serve was painful, to move, to stand, then even to sit. It gets more irritated, more inflamed, more stiff. It was getting worse and worse. It was hard to stay out there.”

Three-time French champion Gustavo Kuerten, who has struggled with hip trouble for years, also was knocked out in the first round. Unseeded and the winner of only two matches this year, Kuerten fell to David Sanchez, 6-3, 6-0, 4-6, 6-1.

A third ex-French champ, Albert Costa, lost to American Vince Spadea. No. 2-seeded Andy Roddick and No. 3 Marat Safin advanced, as did women’s favorite Justine Henin-Hardenne and No. 2 Maria Sharapova.