The International Tennis Federation said on Wednesday it had been assured that no tennis players were part of a Spanish investigation into doping.
A report in a French newspaper earlier this week said leading tennis and soccer players were part of an investigation named Operation Puerto.
"Following reports in the media, the ITF was immediately in touch with the Spanish authorities to request information about allegations that tennis players are under investigation," ITF president Francesco Ricci Bitti said in a statement.
"We have today been assured in writing by the Spanish Ministry of Education and Science that no tennis players, either Spanish or foreign, are under investigation.
"We feel that it is unfair and unfortunate that tennis players, including Rafael Nadal, have been named, erroneously, as under investigation.
"All top players are tested regularly under the Tennis Anti-Doping Programme and are aware of the rules of the World Anti-Doping Agency Code (WADA)
The ITF's statement came a day after the Spanish government categorically denied that footballers and tennis players had been implicated in the doping investigation that hit cycling.
However, the doctor at the centre of the Spanish probe, Eufemiano Fuentes, continued to insist on Wednesday he had treated footballers, athletes and tennis players as well as cyclists.
The names of more than 50 professional cyclists, including Tour de France favourites Jan Ullrich, Ivan Basso and Francisco Mancebo appeared on the report. They were withdrawn by their teams from the race on Friday.
Nadal, who has reached the Wimbledon quarter-finals, reacted angrily to the report.
"I've never taken anything in my life, and I never will," he told reporters this week.
"I'm well enough educated in the sporting world and out of sporting world not to cheat. People who write lies about other people are bad people."