Victorian Premier Daniel Andrews has reintroduced coronavirus restrictions after a Australian Open hotel quarantine worker in Melbourne became infected with Covid, with a testing blitz on tournament participants underway. In a late night press conference on Wednesday, Mr Andrews announced household gathering limits would be slashed in half to 15 and masks would once again be mandatory indoors. About 600 Australian Open players, officials and support staff have been identified as close contacts and are isolating until they test negative for Covid. Most players had only just been released from quarantine. As a result of the testing blitz and isolation orders, all Melbourne Summer Series matches at Melbourne Park on Thursday were cancelled.