ATP chairman Andrea Gaudenzi has called on 'better communication' to be made in relation to doping regulations but insisted Jannik Sinner's case had been handled fairly.

Sinner tested positive twice for the banned substance clostebol at the Indian Wells Open in March.

After a private five-month investigation by the International Tennis Integrity Agency (ITIA), the Italian was cleared of wrongdoing and avoided a ban.

There were calls for Sinner to be provisionally suspended while he was investigated. Despite being cleared, the World Anti-Doping Agency (WADA) are appealing the decision and want Sinner to be banned for potentially two years.

Gaudenzi has now spoken out about the confusion regarding the process and admitted some lessons could be learned about how the issue has been handled.

"We are completely external and it’s [an] independent process. I generally think has been a fair process. It was really done by the book and by the rules," Gaudenzi said.

"Maybe there could have been better communication in explaining those rules, and that is something that I would urge every party involved to work better in the next time.”