Argentina's Mariano Puerta said on Wednesday there is no truth in a report in a French newspaper that he had taken a banned drug and tested positive at the French Open.
"I'm really angry, I've started investigations with my lawyers. This is a very delicate subject, there's no truth in it," said Puerta, the losing finalist at Roland Garros in June.
"It's news to me," Puerta said by telephone from Tokyo. "It's strange because nobody from the ATP or ITF has called me."
Traces of a stimulant called etilefrine were found in a urine sample from Puerta taken after his final defeat by Spain's Rafael Nadal in June, the French sports newspaper L'Equipe said on Wednesday.
"The newspapers can say anything without proof. I haven't taken anything I shouldn't," Puerta said. "If there's an Argentine who was positive let them find him," he said.
"After the [previous] positive I've got to be very careful, I can't even take an orange juice."
Puerta was suspended for nine months after testing positive for banned substance clenbuterol in 2003. He faces a life ban if found guilty of another doping offence.