The case of the world No. 1 in men's tennis is at the center of anti-doping protocols and reforms that could redefine its parameters.

Jannik Sinner received a 3-month ban after testing positive for a banned substance, with the Italian initially refusing to accept he would face a suspension.

The 23-year-old Italian will make his return to action at the Rome Masters 1000 in May, which will also serve him to test his condition ahead of Roland Garros. Having won the Australian Open at the beginning of the year, the ace from Sesto Pusteria can dream of completing the 'Calendar Grand Slam' already this year.

Sinner asked: "Why would we do that if the first independent tribunal found it was no ban at all, why would I accept three months now?"