Craig Tiley, tournament director of the Australian Open, confirmed on Sunday that the first tennis Grand Slam of 2021 will happen as scheduled despite 72 players and their entourages already being quarantined.

"The Australian Open is going ahead and we will continue to do the best we possibly can do to ensure those players have the best opportunity," said Tiley to Nine Network on Sunday.

Positive COVID-19 tests were found in three flights that carried participants to Melbourne. The latest one, which was the fifth in total, was reported on Sunday in the third flight that arrived on Saturday from Doha, carrying 58 passengers. 25 of them are players though the infected passenger is not.

"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 for [practice]," said the Australian Open in a statement.

The other four positive test results came from a broadcaster on the flight from Los Angeles, an aircrew member and a tennis coach on the same plane, plus Sylvain Bruneau, coach of 2019 U.S. Open champion Bianca Andreescu. Bruneau was on the flight from Abu Dhabi.

Players under hard quarantine include Sorana Cirstea of Romania, Belinda Bencic of Switzerland and Yulia Putintseva of Kazakhstan. "If they would have told us this rule before I would not play Australia ... I would have stayed home. They told us we would fly at 20% capacity, in sections and we would be a close contact ONLY if my team or cohort tests positive," posted Cirstea on Twitter.

"We are not complaining to be in Quarantine. We are complaining because of unequal practice/playing conditions before quite important tournaments," tweeted Bencic.

"We are reviewing the schedule leading in to see what we can do to assist these players," said Tiley. The tournament is scheduled to take place between February 8 and 21.