• CAS to hear appeal against tribunal’s original decision
• Italian ‘was not expecting’ Wada to take this action

Jannik Sinner said he was “very disappointed” and “surprised” to be facing the renewed threat of a ban after the World Anti-Doping Agency launched an appeal against a ruling of “no fault or negligence” for two positive tests the world No 1 returned in March.

Sinner, who won the US Open earlier this month, twice tested positive for an anabolic steroid in March but on 20 August an independent tribunal determined he was not to blame and imposed no punishment.