World number seven Matteo Berrettini launched a remarkable resurgence in the fifth set to defeat 17th seed Gaël Monfils and book an Australian Open semifinal with Rafael Nadal.
Berrettini had looked down and out when he lost the third and fourth sets to Monfils, but a double break early in the fifth edged the Italian towards victory.
He went on to triumph over the Frenchman 6-4, 6-4, 3-6, 3-6, 6-2 in a match that did not finish until almost 1:00am AEDT on Rod Laver Arena.
It is the third time the Wimbledon runner-up has reached the semifinals of a major.
Earlier, Nadal survived a serious scare from Denis Shapovalov to earn his spot in a seventh Australian Open semifinal.
The Spanish legend seemed to be cruising through his quarter-final clash when he won the opening two sets, but the Canadian 14th seed hit back to extend Nadal.
Incredibly, Nadal's 6-3, 6-4, 4-6, 3-6, 6-3 win ensured at least one of the 'Big Three' of Nadal, Roger Federer and Novak Djokovic has made the last four for the 70th time in the past 71 majors.
The only time it did not happen since 2004 came at the 2020 US Open when Nadal and Federer did not play and Djokovic was defaulted in the fourth round for recklessly hitting a ball that struck a lineswoman.
But Nadal's victory over Shapovalov did not come easy as he dealt with stomach issues during the match and was in danger of bowing out at the quarterfinal stage of the Australian Open for the third consecutive year.
Without Federer and Djokovic at Melbourne Park, Nadal now has an opportunity to be the first man to win 21 major singles titles.
The three greats are locked on 20 major wins each, but the 35-year-old could reclaim the lead outright by breaking through for his second Open title.
Of all four majors, the first of the calendar year has been Nadal's least successful in terms of silverware.
After defeating Federer in the 2009 final, Nadal has lost four deciders (2012, 2014, 2017 and 2019) on Rod Laver Arena.
On Tuesday, Nadal cruised through the first two sets against Shapovalov, who could not hide his frustration after dropping the opener.
He lost his cool at the umpire early in the second, shouting "You guys are all corrupt", because he believed Nadal should have been called for a time violation.
Shapovalov did regain his composure, however, to force a deciding set but Nadal marshalled his resources off court with a medical timeout and then returned to break serve in the second game to wrest back the momentum.
Shapovalov — who ousted third seed Alexander Zverev in straight sets in the fourth round — was furious with himself after his volley went wide on match point, breaking his racquet in disgust as Nadal celebrated after more than four hours on court.
AAP/ABC
