Danish teenager Holger Rune fought back from a set down to beat hot favourite Novak Djokovic 3-6, 6-3, 7-5 and win his first Masters title in Paris on Sunday.
Djokovic said the Spaniard remains his biggest rival.
Novak Djokovic split with his long-time coach Marian Vajda at the end of the 2021 season, ending one of tennis's most enduring and successful partnerships, the Serbian former world number one said.
'He was a better player I think in important moments.'
Alexander Zverev into ATP Finals semis after straight sets win over Carlos Alcaraz
Here is what you need to know about the prize pot on offer at the 2024 US
Australia scrapped a rule that required international travellers to declare their COVID vaccination status last week.
Serbia have been drawn in Group B alongside Spain, South Korea and Canada.
Novak Djokovic said he would make good on his deal to buy Nick Kyrgios drinks and dinner after beating the Australian to claim a fourth successive Wimbledon title on Sunday.
Unvaccinated players are not barred from participating in Wimbledon
Images from Day 2 of the 2023 Australian Open at Melbourne Park on Tuesday.
Novak Djokovic, who won Wimbledon to take his major singles titles to 21, has opted not to be vaccinated against COVID-19. He said on Thursday he could not fly to New York for the year's final Grand Slam.
Reigning Paris Masters champion Novak Djokovic beat Stefanos Tsitsipas in a three-set epic on Saturday to set up a title clash with Holger Rune, who reached his first ATP Masters 1000 final after a comfortable win over Felix Auger-Aliassime.
Images from Day 3 of the US Open, at Flushing Meadows, New York.
Images from the men's singles action at the US Open on Sunday.
Simona Halep questioned the "big difference" in how doping cases are treated after world number two Iga Swiatek was handed a one-month drugs ban
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.
Djokovic sets sights on Paris Olympics
Carlos Alcaraz suffered a shock 6-1, 7-5 defeat against Norway's Casper Ruud in his opening match at the ATP Finals
Fritz delivers as US win inaugural United Cup crown
Andy Murray's illustrious career finally came to an end as he and doubles partner Dan Evans were beaten 6-2, 6-4 by American pair Taylor Fritz and Tommy Paul in the Olympics quarter-finals at Roland Garros on Thursday.
Rafael Nadal called Novak Djokovic's COVID-19 vaccination controversy in Australia "a circus" and joked that he would prefer that the world number one tennis player didn't play at the upcoming Australian Open.
'I still feel my body is serving me, is listening to me well. That's the key I think when you get to 35-plus.'
The Serbian champion said he hoped the focus would now return to tennis
Rafael Nadal has decided not to participate in the US Open due to concerns about his fitness
Djokovic was deported from Australia, just hours after the court dismissed his effort to stay in the country to play at the Australian Open
Nadal has won the Australian and the French Open back-to-back and has the chance to become the first man to win all four majors in the same year
Top seed Novak Djokovic set up a blockbuster Wimbledon final against Nick Kyrgios after recovering from a torrid start to overwhelm Britain's Cameron Norrie 2-6, 6-3, 6-2, 6-4 on Friday.
Novak Djokovic has only faced Nick Kyrgios twice in his career, losing twice to him in 2017, so while he will be favourite to claim a seventh Wimbledon crown, he knows exactly how dangerous the unpredictable world number 40 Kyrgios can be.
Novak Djokovic said on Friday he would like to return to play in Australia again despite being deported from the country earlier this year
'I'm happy to be part of this Italian movement. People, they start to play tennis now more and more, which is great to see. I think that's the most important.'
World number one Novak Djokovic earned his 1,000th tour-level victory by beating Casper Ruud 6-4, 6-3 on Saturday to reach the Italian Open final.
It may not quite be the end for British great Andy Murray at Wimbledon but it felt like it as the 37-year-old received an emotional farewell after he and brother Jamie were beaten in the first round of the men's doubles on Thursday.
Novak Djokovic will spend Saturday night in immigration detention before the world's tennis number one seeks a court ruling to stop his deportation and keep alive his bid for a record 21st major title at the Australian Open.
Spanish teenager Carlos Alcaraz came from behind to beat world number one Novak Djokovic 6-7(5), 7-5, 7-6(5) to reach the Madrid Open final, where on Sunday he will face Alexander Zverev after the German defeated Stefanos Tsitsipas 6-4, 3-6, 6-2.
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.
There is a petition circulating to allow Novak Djokovic to play at the US Open but the Serbian appears likely to miss the entire North American hardcourt swing barring a sudden change in COVID-19 protocols in the United States and Canada.
The ATP Tour brought the world number ones for a short conversation as they prepared for the prestigious tournament.
Immigration Minister Alex Hawke's office said he was still considering whether to use his discretionary power to cancel Novak Djokovic's visa.
Jannik Sinner's stupendous year may have been clouded by an anti-doping controversy but on the court he is finishing the season like an express train and has won 25 of his last 26 matches.