Organisers of the Australian Open in Melbourne are reportedly considering introducing a COVID-19 vaccine mandate in a move which could prevent a number of the top players from participating at the first tennis Grand Slam of the year.

accepted the decision in talks with the Government.World number one and defending Australian Open champion Novak

Djokovic is among the players who have signalled their opposition to mandatory vaccines, which have

Slam champion has declined to answer questions regarding his own vaccination status.World number one Novak

Djokovic is among the players opposed to mandatory COVID-19 vaccines ©Getty ImagesGreece's world number

World number two Aryna Sabalenka has pulled out of the Indian Wells Masters after testing positive for COVID-19.

Naomi Osaka has also pulled of the tournament as she is taking a break from tennis.Men's number one Novak

Djokovic is also not competing."

Stefanos Tsitsipas has confirmed he is planning to get vaccinated against COVID-19 after being criticised by the Greek Government over his reluctance to be inoculated.

The COVID-19 vaccine has also divided opinion in tennis.In April, world number one Novak Djokovic said

broadcaster ESPN's coverage of Emma Raducanu’s victory over Leylah Fernandez than Daniil Medvedev ending Novak

Slam in a straight-sets win against fellow teenager Fernandez of Canada.The following day saw Serbia’s Djokovic

Novak Djokovic's quest to win all four Grand Slams in a calendar year was ended at the last hurdle by

World number Djokovic one was irritable and seemingly not 100 per cent fit at the showpiece Arthur Ashe

past three sets only once en route to the final in New York City - whereas 20-time Grand Slam champion Djokovic

went unbroken through the opening two sets to move one away from victory.And when Medvedev twice broke Djokovic

in the 2016 US Open final.The Big Three - Swiss great Roger Federer, Spain's Rafael Nadal and Djokovic

- have each won a record 20 men's singles Grand Slam titles, and Djokovic squandered his chance to move

Only Russia’s Daniil Medvedev stands in Novak Djokovic’s way of history after the Serbian world number

Djokovic has won all three Grand Slams so far this year, and is looking to becoming the first man since

reach his second consecutive final in New York City.For the fourth successive match at the US Open, Djokovic

-2 and 6-4.It was then Zverev’s turn to rally as he clinched the fourth 6-4 to force a decider, but Djokovic

There is only one match left - all in," Djokovic said.Daniil Medvedev has dropped only one set so far

New York City two years ago, losing in five sets to Nadal, while he was beaten in straight sets by Djokovic

World number one Novak Djokovic of Serbia set up a US Open semi-final against Germany’s Olympic champion

Djokovic moved within two wins of becoming the first man since Rod Laver in 1969 to win all four of the

during the night session at Arthur Ashe Stadium in New York City.In a repeat of July’s Wimbledon final, Djokovic

behind in the first set to the world number eight, with Berrettini taking it 7-5.However, the formidable Djokovic

It was a great match," Djokovic said afterwards."

 The 24-year-old came from behind to beat Djokovic in the semi-finals of this summer’s Tokyo 2020

Players who plan to compete at next year's Australian Open in Melbourne will face tougher measures if they are not vaccinated against COVID-19, they have been warned.

would only get vaccinated for COVID-19 if it became mandatory to compete in tennis.World number one Novak

Djokovic said in April, meanwhile, that he hoped the COVID-19 vaccine would not become mandatory for

Second seed Daniil Medvedev advanced to the US Open men’s singles semi-finals after ending the run of Dutch qualifier Botic van de Zandschulp in New York City, and will face Canada's Felix Auger-Aliassime in the last four.

maiden Grand Slam title, after being beaten by Austria’s Dominic Thiem in 2020 and losing the Serbia’s Novak

Djokovic in the Australian Open final earlier this year.Canada's Felix Auger-Aliassime had led 6-3,

Germany’s Olympic champion Alexander Zverev against South Africa’s Lloyd Harris, and world number one Djokovic

World number two Daniil Medvedev of Russia was in scintillating form in his fourth round men’s singles clash against Britain’s Dan Evans at the US Open as he cruised through in straight sets, while Dutch qualifier Botic van de Zandschulp stunned Argentina’s Diego Schwartzman.

to Spain’s Rafael Nadal in the final in New York two years ago and been denied by world number one Novak

Djokovic of Serbia in the Australian Open at the start of this year.Medvedev is looking forward to being

World number one Novak Djokovic continued his search for a calendar Grand Slam with a victory against

Djokovic is looking to become the first man for more than 50 years to win all four of the men’s tennis

Women's singles top seed Ashleigh Barty is safely through to round three of the US Open along with Olympic champion Belinda Bencic.

Wimbledon runner-up earlier in the year - also won in four sets to reach round three.Men's top seed Novak

Djokovic also secured safe passage into the third round.The Serbian, who was heckled at one stage as

Former Women's Tennis Association (WTA) world number one Victoria Azarenka of Belarus has called for COVID-19 vaccinations to be made mandatory for players on the WTA Tour.

Rafael Nadal have both received and encouraged vaccinations.On the other hand, men’s world number one Novak

Djokovic of Serbia has said he would oppose any move to make vaccines compulsory.The Greek Government

Russian duo Daniil Medvedev and Andrey Rublev continue to march on in the US Open with dominant displays in the men's singles second round at Flushing Meadows in New York.

champion Alexander Zverev is due to face Spain’s Albert Ramos Viñolas, and Serbia’s world number one Novak

Djokovic is set to play The Netherlands' Tallon Griekspoor in the top half of the second round draw.

blitzed Sam Querrey in straight sets to progress to the US Open second round, while world number one Novak

Djokovic started his campaign for a calendar Grand Slam with victory over Holger Rune in New York City