The World Anti-Doping Agency (WADA) has lodged an appeal to the Court of Arbitration for Sport (CAS) in the doping case of Italian tennis world number one Jannick Sinner, the agency said on Saturday. WADA said in a statement the appeal was filed on Thursday. It comes after Sinner escaped a ban by a tennis agency despite two positive tests for a banned steroid. The International Tennis Integrity Agency (ITIA) revealed in August that the Italian tested positive twice for low levels of clostebol in March, a few weeks after his first grand slam title at the Australian Open. The ITIA absolved Sinne…