Novak Djokovic blamed "human error" on Wednesday for a mistake in his Australian immigration paperwork and apologised for breaking isolation for a photoshoot when he had COVID-19 last month.

Homeland favorite Ashleigh Barty and Serbia's Novak Djokovic are the top seeds for the upcoming Australian Open.

Immigration Minister Alex Hawke's office said he was still considering whether to use his discretionary power to cancel Novak Djokovic's visa.

Djokovic's family said his release was the 'biggest victory of his life'.

At one stage, police deployed pepper spray.

World number one Novak Djokovic was released from Australian immigration detention on Monday after winning a court challenge to revive his bid to win a record 21st Grand Slam title at the upcoming Australian Open.

Australian authorities scrambled on Sunday to file a legal defence of their decision to bar entry to tennis world number one Novak Djokovic over his COVID-19 vaccination status, as the Serbian superstar spent his fourth day in immigration detention.

Djokovic, who is seeking to win a record 21st Grand Slam title at the tournament this month, said in a legal challenge on Saturday that he had been given the medical exemption because he had contracted COVID-19 last month.

Djokovic, a vocal opponent of vaccine mandates hoping to win his 21st Grand Slam at the Australian Open, has been holed up since Thursday in a modest Melbourne hotel after his visa was cancelled due to problems with the exemption.

Australia's Nick Kyrgios said he supported vaccination "but how we are handling Novak's situation is bad, really bad". The Australian Open begins on January 17, but the multi-millionaire Djokovic is constrained from training as he sits in a hotel where one Iranian detainee said he had found maggots and mould in the bread.

Tennis World No. 1 Novak Djokovic spent Orthodox Christmas in Australian immigration detention on Friday as his lawyers fought a government decision to remove him from the country that could scupper his shot at a record-breaking 21st Grand Slam.

The 34-year-old is currently housed in a government detention hotel in the suburb of Carlton, 5 km (2 miles) north of Melbourne Park, after authorities cancelled his visa when he arrived in Australia.

The arrival of Novak Djokovic led to incongruous scenes outside the hotel, with members of the Serbian expatriate community draped in the national flag and playing traditional music joining refugee activists in protests.

'This has nothing to do with sports, this is a political agenda. Novak is the best player and the best athlete in the world, but several hundred million people from the West can't stomach that.'

Novak Djokovic will spend at least the next 72 hours in a Melbourne hotel before the next hearing in his fight to overturn a ban on entering Australia is held on Monday.

World number one tennis player Novak Djokovic was denied entry into Australia on Thursday amid a storm of protest about a decision to grant him a medical exemption from COVID-19 vaccination requirements to play in the Australian Open.

Djokovic, who has won nine titles at Melbourne Park, including the last three, confirmed on Tuesday that had received a vaccination exemption to allow him to bid for a record 21st major title at the Australian Open, which starts on January 17.

Djokovic announced on Tuesday he received an exemption to play in the Grand Slam tournament in Melbourne and said he was heading to Australia.

Officials said he was one of a 'handful' of successful applicants among 26 people who sought exemptions.

World number one Novak Djokovic said on Tuesday he would defend his Australian Open title at Melbourne Park later this month after receiving a medical exemption from getting vaccinated against COVID-19.

Novak Djokovic has pulled out of the Serbia team for the ATP Cup in Sydney, event organisers said on Wednesday, raising further doubts over whether the world number one will defend his Australian Open title next month.

Djokovic has declined to disclose whether he is vaccinated, citing privacy.

In the third-tier Europa Conference League, English Premier League club Leicester City will face Danish side Randers and Scottish club Celtic will take on Norwegian champions Bodo/Glimt in the knockout playoff round.

Russia took an unassailable 2-0 lead over Croatia in the Davis Cup final in Madrid on Sunday to secure their third title and first in 15 years, as Daniil Medvedev outlasted Croatian Marin Cilic 7-6(7), 6-2.

Serbia had their backs to the wall when Kazakh veteran Mikhail Kukushkin beat debutant Miomir Kecmanovic in a three-hour epic in the first singles rubber. But Djokovic calmly levelled the tie with a straight-sets defeat of Alexander Bublik before returning to court to team up with Nikola Cacic and beat Kazakh pair Andrey Golubev and Aleksandr Nedovyesov 6-2, 2-6, 6-3.

Tennis great and founder of the WTA Billie Jean King was among those who applauded the announcement.

Favourites Russia Tennis Federation opened their Davis Cup Finals campaign with a resounding victory over Ecuador, Britain began with a win against France and Italy eased into the quarter-finals with a win over Colombia on Saturday.

Djokovic says Peng situation horrifying, says tennis must unite.

Friday's match was a straight shootout for a last-four place, with world number five Rublev the favourite having won his four previous matches against Ruud.

Alexander Zverev booked his place in the last four of the ATP Finals where he will face world number one Novak Djokovic after a 6-2, 6-4 win over Hubert Hurkacz in Turin on Thursday.

Novak Djokovic, the world number one ranked men's player, has reiterated his stand about freedom of choice over taking the COVID-19 vaccine as suspense grows over his participation at the Australian Open in January.

Australian government officials have said unvaccinated players will be barred from the tournament in January, casting doubt on whether men's world number one and reigning champion Novak Djokovic will defend his title.

American great Pete Sampras said he does not expect any player to match Novak Djokovic's feat of winning the men's year-end world number one ranking seven times.

Jubilant fans thronged central Belgrade, bringing traffic at the main Republic Square to a halt as they waved Serbian flags and hooted their car horns.

Federer is tied with Rafael Nadal and Novak Djokovic in the race to be the most successful men's singles Grand Slam champion of all time and Australian Open organisers would have been hoping to have all three at Melbourne Park.

Novak Djokovic won a record-extending sixth Paris Masters title by avenging his U.S Open final defeat against Russian Daniil Medvedev with a 4-6, 6-3, 6-3 victory in Sunday's showpiece match.

The Russian ended Djokovic's hopes of completing a sweep of all four Grand Slam titles in 2021 when he defeated the Serb in the US Open final in September to pick up his maiden major.

World number one Novak Djokovic had to work hard for a three-set victory over Hungarian Marton Fucsovics at the Paris Masters on Tuesday in his first match since losing the U.S. Open final in September.

World number one Novak Djokovic once again declined to reveal whether he has been vaccinated against COVID-19 and said he is unsure if he would defend his title at next year's Australian Open.

The agony and ecstasy of the Mumbai Indians-Royal Challengers Bangalore IPL 2021 encounter was best captured on the MI-RCB players's wives at the Dubai cricket stadium, September 26, 2021.