The 16-times Grand Slam champion, who has been slightly ill lately, was kept on his toes before racing to victory to set up a meeting with seventh seed Stefanos Tsitsipas.
The coronavirus has however infected increasing numbers of athletes and others involved with the Games, and authorities were on Friday trying to track down a Ugandan weightlifter who went missing from his training camp.
'Generally, I'm happy outside the court, happy on the court, happy in life. Then I think you play your best.'
Kyrgios out of Australian ATP Cup team as world ranking slips.
Australia's Alexei Popyrin was the last man standing, losing 7-6 (3), 6-3, 6-7 (10), 4-6, 6-3 to France's Lucas Pouille in their third round match.
The ninth seeded Indo-Romanian rallied to shock the three-time champions 5-7, 6-4, 7-6(9), 7-6(5) in their quarter-final match.
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.
IMAGES from Day 4 of the Wimbledon Champions at the All England Lawn Tennis and Croquet Club, London, on Thursday
This year's ATP Finals boasts a fresh new
Australia eased ahead of Bosnia 2-0 as John Millman thumped Damir Dzumhur 6-3, 6-2 while Alex de Minaur overcame Mirza Basic 6-3, 7-6(0), before Millman revealed the team's larger goal under captain Lleyton Hewitt.
Images from Day 3 of the French Open in Paris on Tuesday
It ended a woeful few days for reigning champions Croatia. They left with two losses.
On Saturday, the young guns showed no signs of breaking the stranglehold of the three men who collectively own 50 Grand Slam titles and also split the season's first three majors.
American qualifier Sachia Vickery completed an astonishing comeback to stun third seed Garbine Muguruza 2-6, 7-5, 6-1 in a second-round win at the BNP Paribas Open in California on Friday.
It was a repeat of the 34-year-old's straight sets victory over Andy Murray in the second round of the US Open in August.
Czech defending champion Katerina Siniakova fended off Maria Sharapova in a fiercely contested match at the Shenzhen Open on Friday to set up a final with world number one Simona Halep.
But for the first time, that golden trio will be having an anxious glance over their shoulders. The past week in London has revealed a new fearlessness in the generation of 20 somethings expected to fill the void when they call it a day.
Rafael Nadal kept the flag flying for the old guard at the Australian Open with a 6-3, 6-4, 6-2 victory over American Frances Tiafoe on Tuesday for a place in the semi-finals, where he will meet another next generation player in Stefanos Tsitsipas.
Former world number one Andy Murray won his first ATP tour singles match in nearly nine months with a 6-3, 6-7(6), 6-1 victory over American Tennys Sandgren in the opening round of the Zhuhai Championships.
Twice Shanghai Masters champion Roger Federer was far from his best against Spain's Roberto Bautista Agut but did enough to reach the quarter-finals with a 6-3, 2-6, 6-4 win on Thursday.
Rafael Nadal will skip the Miami Open that begins later this month in a bid to recover from a back injury in time for the clay court swing
A look at the records of Spain's Rafael Nadal and Serbia's Novak Djokovic before their title clash at the Australian Open on Sunday (prefix number denotes seeding):
On the 10th anniversary of the 2008 Wimbledon men's final that is widely considered the 'greatest ever tennis match' it seems like the stars may be aligning for Roger Federer and Rafael Nadal to meet in another mesmerising epic.
Images from Day 3 of the French Open matches played at Roland Garros on Tuesday
World number one Rafael Nadal won a battle of attrition against fellow left-hander Yoshihito Nishioka of Japan 7-6(4), 6-4 to seal Spain's spot in the final eight of the inaugural ATP Cup in Perth on Wednesday. Meanwhile his long-time rival, world number two Novak Djokovic, had an easier outing in Brisbane, strolling past Chile's Cristian Garin 6-3, 6-3 to stay undefeated in the new year.
Images from Day 7 at the US Open.
Summary of sports events and persons who made news on Thursday
IMAGES from Day 3 of the US Open in New York on Wednesday.
Summary of sports events and persons who made news on Monday
After a brief interruption when the players were locked at 5-5 in the opening set, Federer saved two set points in the tiebreak and held firm to gain the upper hand in the contest.
Big-serving Isner reaches Montreal second round
IMAGES from the Australian Open matches played at Melbourne Park on Wednesday
Australian great Rod Laver is as impressed as anyone while watching Rafael Nadal tear into the fourth round of Wimbledon on Saturday to stay on track for a third title.
Venus Williams staged a spirited comeback to down third seed Petra Kvitova 4-6, 7-5, 6-4 and reach the third round of the BNP Paribas Open in Indian Wells on Saturday.
It was Kristyna's first win over a top-five ranked player and she will go on to play fellow Czech Barbora Strycova in the quarter-finals.
IMAGES from the matches played during the Wimbledon Championships at the All England Lawn Tennis and Croquet Club, at Wimbledon in London on Thursday
A summary of sports events and sports persons, who made news on Friday.
Images from the third day at the US Open, the final Grand Slam tournament of the year, in New York, on Wednesday:
Thursday's match was just Venus Williams's seventh of the year and first since January's Australian Open, where she fell to Simona Halep in the round of 32.
Images from Day 2 of the Australian Open in Melbourne on Tuesday