World number 30 Berrettini saved five points in the marathon second set tiebreak and held on to win it 13-11 for his third ATP crown in last 11 months.
While Federer and Nadal will look to reignite the flair and fight they showed to reach last year's final, 2018 could have a different script at play.
Andy Murray said he hoped the players and their family members who tested positive recovered soon and added that the tournament should not have gone ahead in hindsight.
India ended its campaign at the Fed Cup with a fourth place finish after losing the classification tie 1-2 to Korea as the team badly missed injured Karman Kaur Thandi, who did not play on Saturday, in Astana, Kazakhstan.
Spanish teenager Carlos Alcaraz beat Norway's Casper Ruud 6-4, 2-6, 7-6(1), 6-3 in the men's singles final at the US Open on Sunday to win his maiden Grand Slam title and rise to world number one for the first time.
Swiss teenager Belinda Bencic capped a brilliant run to the Rogers Cup title on Sunday.
No complaints but quarantine differentials were a mistake: Zverev
Images from Day 4 of the Australian Open in Melbourne on Thursday.
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.
Klitschko and his brother Vitali, also a former world heavyweight champion and now the mayor of Kyiv, have both taken up arms against invading Russian forces.
Holger Rune crashed out to Yoshihito Nishioka in the ATP 250 Adelaide International 1 first round.
The 36-year-old Swiss will play Canada's Milos Raonic in Sunday's final.
The 2020 international calendar concluded with the three tournaments in the Asia leg which was conducted in Bangkok in successive weeks.
Summary of sports events and persons who made news on Sunday
Drained Medvedev pulls out of home tournament in Moscow
Simona Halep ended Beatriz Haddad Maia's dream run in Toronto
India's Davis Cup captain Mahesh Bhupathi on Thursday defended the selection of N Sriram Balaji ahead of higher-ranked Jeevan Nedunchezhiyan and Purav Raja for the tie against Serbia.
Images from Monday's action at the Australian Open.
Ankita is now country's best-ranked singles (182) and doubles (95) player and is set to make her Olympic debut at the Tokyo Games next month.
Huge upsets lit up the basketball World Cup on Wednesday as France beat hosts Spain 65-52 while Serbia thumped Brazil 84-56 to set up an intriguing semi-final clash.
'I LOVE YOU, Roger. Thank you for everything you've done in tennis and with myself. Tennis world will never be the same without you.'
Indian Davis Cupper Prajnesh Gunnewaran, on Wednesday, earned the biggest win of his career by stunning world number 23 Denis Shapovalov in the opening round of the ATP Mercedes Cup in Stuttgart.
Roger Federer has his sights set on ending the year as the world's top-ranked player after the 33-year-old claimed his fifth title of the year in his home town.
Roger Federer is keeping a lid on expectations.
Shapovalov made the world take note of him with his shock win over Rafael Nadal at the Montreal Masters. He then became the youngest player to reach the fourth round of the US Open, only his second Grand Slam, last week.
Nagal said he would look to play more ATP Tour events this year but for that he would have to first improve his rankings.
It took the COVID-19 pandemic to put a brake on Djokovic's 18-match unbeaten run in 2020, as he won the ATP Cup with Serbia, an eighth Australian Open title and a fifth Dubai Tennis Championships before the season came to a halt in early March.
The evening start for the Davis Cup tie against Spain has caught the Indian team by surprise with captain Anand Amritraj calling it an 'unfortunate' decision that has compromised the country's home advantage.
David Ferrer won his third consecutive Buenos Aires ATP claycourt title, and the sixth in a row by a Spaniard, when he beat Italian Fabio Fognini 6-4, 6-3 in the final on Sunday.
The 23-times Grand Slam champion looked a completely different player from the person who smashed her way into the semi-finals of the doubles with Caroline Wozniacki on Wednesday but managed to do just enough to beat the 86th-ranked McHale.
The professional tennis circuit, which requires players to jet around the world, was forced into shutdown in early March as countries went into lockdown and closed their borders to contain the spread of the novel coronavirus.
Manchester City and Everton players took to the field wearing Ukrainian flags before their Premier League game on Saturday while there were anti-war messages at stadiums elsewhere following Russia's invasion of Ukraine.
It was Novak Djokovic's first match this year after his Australian Open hopes were dashed when he was deported following an 11-day saga revolving around his decision not to have a COVID-19 vaccination.
Veteran star Leander Paes is set to combine with Rohan Bopanna for the doubles rubber during the Davis Cup tie against Serbia, Indian captain Anand Amritraj confirmed today but he says nothing has been decided on the Asian Games squad as yet.
Andy Murray and Rafael Nadal were winners but six seeds were beaten in a day of upsets in the second round at the Rogers Cup in Montreal on Thursday.
In winning the Davis Cup Andy Murry has fulfilled the hopes Britain had in him. Now, says Bikash Mohapatra/Rediff.com, he needs to live up to his initial promise and consistently deliver results a player of his potential deserves.
The Indian Davis Cup team is set for a battle of gigantic proportions as it takes on five-time champions Spain, who have packed the side with world class performers headlined by the legendary Rafael Nadal in their desperation to reclaim a spot in the elite World Group.
Novak Djokovic sauntered past Spaniard Feliciano Lopez to reach the quarter-finals of the Shanghai Masters on Thursday but Andy Murray had to claw past big-serving American John Isner after losing a first-set tiebreaker.
Austrian Dominic Thiem became the first player to capture titles on three different surfaces this year when he finished off Philipp Kohlschreiber to win the Mercedes Cup in Stuttgart on Monday.
A long season took its toll on Roger Federer on Thursday as the Swiss was knocked out of the Paris Masters following a 7-6(3) 3-6 7-6(5) third-round defeat by big serving John Isner.