MELBOURNE: Australian Open chief Craig Tiley insisted Sunday the Grand Slam tournament would still begin next month, but problems mounted for organisers as another 25 players were quarantined for two weeks.

A total of 72 players are now confined to their hotel rooms in Melbourne for 14 days, and barred from practising, after coming into contact with Covid-19 cases on flights to Australia. The tournament was thrown into disarray on Saturday when three people tested positive to Covid-19 on two of the 17 charter flights bringing players and their entourages to Melbourne and Adelaide.

A fourth person, a member of a broadcast team on one of the flights, from Los Angeles, tested positive Sunday. None were players, although one was Sylvain Bruneau, coach of Canada's 2019 US Open winner Bianca Andreescu. Another was also a coach. Everyone on board was considered to be close contacts and ordered not to leave their hotel rooms for the 14-day quarantine period.

On Sunday, a further 25 players were ordered into quarantine after a passenger on their flight from Doha to Melbourne tested positive for coronavirus, having tested negative before boarding. "The 25 players on the flight will not be able to leave their hotel room for 14 days and until they are medically cleared. They will not be eligible to practise," the organisers said in a statement on Twitter.

That means the 72 quarantined players will not be allowed out to train for five hours a day as previously agreed in the build-up to the opening Grand Slam of the year, due to start on February 8.