Denis Shapovalov upset an out-of-sorts Alexander Zverev 6-3, 7-6(5), 6-3 in broiling heat to reach his first Australian Open quarter-finals on Sunday.
The Canadian left-hander was magnificent against the German third seed, earning one of his biggest career victories at Margaret Court Arena.
Shapovalov blew a match point with a wild forehand into the tramlines but wrapped up the contest when Zverev netted under pressure.
"Definitely happy with where the game is at," said the ecstatic 22-year-old, long tipped for success at the Grand Slams.
"I think off the ground I was just really playing very well, really feeling my shots off both wings."
The 14th seed will meet Rafael Nadal for a place in the semi-finals.
"It's always an honour to go up against a guy like Rafa," Shapovalov said of the Spanish great, who is bidding for a record 21st Grand Slam title.
"It's always going to be a battle against him. It's going to be a tough one but I'm going to enjoy it."
It was a disappointing exit for Zverev, who was bundled out of the quarter-finals by Novak Djokovic last year.
Late last year Zverev suggested he and Russian Daniil Medvedev might become part of a new 'Big Three' with world number one Djokovic in the 2022 season.
Nadal beats Mannarino in battle of left-handers to reach last eight
Rafael Nadal remained on course for a men's record 21st Grand Slam title after winning a battle of left-handers against France's Adrian Mannarino 7-6(14), 6-2, 6-2 to also reach the quarter-finals.
The only former champion left in the men's draw, 2009 winner Nadal is tied on 20 majors with injured Roger Federer and nine-times Melbourne Park winner Novak Djokovic, who was deported from Australia before the tournament began.
Mannarino had lost both his previous meetings against Nadal and came into the contest after a demanding third-round victory over Russian Aslan Karatsev in a match that lasted four hours and 39 minutes.
And after an intense opening set, which included a 30-point tiebreaker and lasted 81 minutes, the 69th-ranked Frenchman wilted under the blazing afternoon sun at the Rod Laver Arena as Nadal sealed the win with an ace on his first match point.
The former world number one will next meet another left-hander in Denis Shapovalov of Canada for a place in the semi-finals.
Rejuvenated Monfils takes Kecmanovic in his stride
Gael Monfils's blistering start to the season continued on Sunday as he eased past Serbian Miomir Kecmanovic 7-5, 7-6(4), 6-3 to reach his second Australian Open quarter-finals.
With wife and top women's player Elina Svitolina beaming in the crowd, the flamboyant Frenchman lit up the Margaret Court Arena with sparkling shot-making to reach the last eight at Melbourne Park for the first time since 2016.
"It was really tough, he played extremely fast on both sides," said 17th seed Monfils, who will play Matteo Berrettini, who beat Pablo Carrena Busta 7-5, 7-6(7-4), 6-4 for a place in the semi-finals.
"I tried to be very aggressive today ... It was just battling, battling, hanging in there."
Monfils wrapped up the match with trademark panache, leaping high to thump a backhand crosscourt winner and end Kecmanovic's dream run since the Serb avoided a first-round clash against the deported world number one Novak Djokovic.
At 35 and recently married, Monfils has a new lease on life, and wants to go even further in the tournament.
"I want to do better .... We are not quite finished yet," he said.
Berrettini serves big to see off Carreno Busta
World number seven Matteo Berrettini defeated Spain's Pablo Carreno Busta 7-5, 7-6(4), 6-4 to reach the Australian Open quarter-finals for the first time.
Berrettini, coming off a marathon five-set win over Carlos Alcaraz, showed no signs of fatigue as he struck 57 winners including 28 aces against Carreno Busta on a warm evening at Rod Laver Arena.
He has now reached the quarter-finals at all four Grand Slams, becoming only the 10th active player to achieve the feat.
"I was really precise. I think he (Carreno Busta) wasn't reading my serve and that's why I did a lot of aces," Berrettini said.
"When my serve is working, it's always good for my tennis."
Berrettini broke Carreno Busta in the 11th game of the opening set after two successive net cords went his way. The Italian saved a break-point in the next game before firing some big serves to wrap up the first set.
He dominated on his serve in the second set and won the tiebreaker with the help of three aces.
Busta showed fight in the contest but could not match Berrettini, who won 87 per cent points on his first serve and wrapped up the match in two hours and 22 minutes.
Berrettini, who withdrew from his fourth-round match at Melbourne Park last year due to an abdominal injury, will face Gael Monfils in the last eight after the Frenchman defeated Serbia's Miomir Kecmanovic.
The 25-year-old beat Monfils in a five-set thriller at the US Open in 2019 to reach his first Grand Slam semi-final.
"It was a really tough match and I think the emotions were all over the place for me and him (Monfils)," Berrettini said.
"I always remember that match with a smile but I know it's going to be a different match this time.
"He's playing good, I'm feeling good, so for sure, it's going to be a fight, we know each other pretty well."