Jannik Sinner’s long doping saga came to an end on Saturday after he agreed to a three-month ban from tennis, the world number admitting “partial responsibility” for team mistakes which led to him twice testing positive for traces of clostebol in March last year.In a statement, Sinner said that the World Anti-Doping Agency (WADA) accepted that he “had no intent and did not derive any competitive advantage from the two positive tests” of the banned substance.