PARIS – There was none of the usual red-clay and Parisian romance yesterday as Mariano Puerta, an unseeded and uncelebrated Argentine, progressed into the semifinals at Roland Garros for the first time.

The run from Puerta has caught almost everybody by surprise. The lefthander has been saying that his run of form here has been partly inspired by a doping ban, having tested positive for a banned steroid two years ago. He is still propelled by what he sees as the injustice of a nine-month suspension, issued after he was found with clenbuterol in his system, and only completed in July last year.

Puerta returned with a ranking in the 400s, and just seven months ago was playing in a Futures event, two levels below the full circuit.

Now he finds himself in the last four of the French Open. Puerta claimed that the drug had been prescribed to treat his asthma attacks, and he said that he has inadvertently been “helped” by the doping offense.

“I am enjoying myself because of all my experiences, because of all the things that I have been through. All the things that have happened have strengthened me,” he said.

Puerta has suddenly emerged through the draw, coming from two-sets-to-one down against Guillermo Canas, a fellow Argentine and the ninth seed, to win 6-2, 3-6, 1-6, 6-3, 6-4. He will play Russian Nikolay Davydenko, who converted his fourth match point for a 3-6, 6-1, 6-2, 4-6, 6-4 victory over Tommy Robredo. The Spaniard finished the match smeared in clay and hurling his racket in frustration from the baseline to the net; indeed, it was a day of long rallies and even longer faces.

It is the second successive year at Roland Garros that an Argentine player has reached the latter stages after serving a ban for a doping offense. Last season’s beaten finalist, Guillermo Coria, was suspended for seven months in 2001 after he tested positive for nandrolone. Juan Ignacio Chela, a third leading Argentine and a quarterfinalist last year, was banned for three months in 2001 after failing a drug test.

Puerta escaped the maximum two-year ban after persuading the tribunal that the substance he had taken was one medically prescribed to him to help to overcome his asthma, claiming that he had “a particularly acute attack” when his 18-year-old niece underwent heart surgery. He maintains that his only mistake was not to inform the ATP Tour that he suffered from asthma.

Puerta had a fast start against Canas, but a match between these two Argentines was never going to be anything other than five sets of grinding, grunting, and all-consuming effort. There was hardly a lob or a drop-shot in sight, with both giving the ball such an almighty whack, their shots thudding and fizzing off the red clay.

All four men’s semifinalists will be making their debuts in the penultimate round of the French Open, but there is every reason to suppose that the winner of Roger Federer and Rafael Nadal will go on to defeat the winner of Puerta and Davydenko. With Federer and Nadal at the top of the draw, there was always a slight sideshow feel to the bottom half.