Precocious Canadian talent Felix Auger-Aliassime looks perfectly placed to make a run deep into the Australian Open, coming back from two sets down against Alex Molcan to book his spot in the third round.
The top half of the draw was blown wide open on Wednesday following Rafael Nadal's dramatic loss to American journeyman Mackenzie McDonald after the 22-time major winner suffered a hip injury.
Nadal returned to Rod Laver Arena after a medical timeout, but was clearly hampered in the 6-4 6-4 7-5 loss.
Sixth-seeded Auger-Aliassime is among the contenders in best position to take advantage of Nadal's shock exit, along with Stefanos Tsitsipas, Daniil Medvedev, Hubert Hurkacz and Jannik Sinner.
But the Canadian had to do it the hard way against Molcan, dropping the first two sets before lifting to win 15 of the last 19 games in a 3-6 3-6 6-3 6-2 6-2 triumph against the increasingly-frustrated Slovakian.
"When I won the third set I got a lot more self-belief," said Auger-Aliassime.
"I'm very pleased to get it done. It was a tough day for me."
Auger-Aliassime will next play No.28 seed Francisco Cerundolo from Argentina, who beat Frenchman Corentin Moutet 3-6 6-4 6-2 7-5.
The 22-year-old enjoyed a breakout year in 2022, winning his first four Tour-level titles.
He also reached the quarter-finals at Melbourne Park last year before falling to eventual runner-up Daniil Medvedev.
Italian Sinner enjoyed a much more comfortable path into the third round, needing just one hour, 44 minutes to see off the challenge of Argentina's Tomas Martin Etcheverry 6-3 6-2 6-2.
The 15th seed has made a flying start to the opening grand slam of the year, dropping just 13 games in total in his two wins over Britain's Kyle Edmund and Etcheverry.
He did not face a single break point against the Argentine world No.79.
"I'm very happy to be in the next round," said the 21-year-old Sinner, who is co-coached by Australian Darren Cahill.
"I'm very happy to play again on this court with the roof, especially as it's raining outside.
"I served well and also returned well today."
Sinner will play Marton Fucsovics from Hungary in the round of 32.
Greece's No.3 seed Tsitsipas and No.16 seed Francis Tiafoe, from the United States, also advanced in comprehensive fashion.
Tsitsipas breezed past local fan favourite Rinky Hijikata 6-3 6-0 6-2, while Tiafoe crushed Chinese qualifier Shang Jungcheng 6-4 6-4 6-1.
Tsitsipas will face Dutch player Tallon Griekspoor in the third round, with Tiafoe set to take on 18th seed Karen Khachanov.
Canadian Denis Shapovalov was a 6-3 7-6 (7-3) 7-5 winner over Japan's Taro Daniel and will next face Pole Hurkacz, who went the distance in a 3-6 7-6 (7-3) 2-6 6-3 6-3 win over Italy's Lorenzo Sonego.
No.7 seed Medvedev accounted for Australian veteran John Millman 7-5 6-2 6-2 to set up a meeting with 29th seed Sebastian Korda, who beat Japanese qualifier Yosuke Watanuki 6-2 7-5 6-4.
With his match having stretched beyond three hours at 1.28am, Cameron Norrie, Britain's No.11 seed, was relieved to finally see off Frenchman Constant Lestienne 6-3 3-6 7-6 (7-2) 6-3.