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MELBOURNE, Feb 8 (Reuters) - Canadian 11th seed Denis Shapovalov outlasted Italian Jannik Sinner 3-6 6-3 6-2 4-6 6-4 in an enthralling battle of 'Next Gen' stars on Monday to move into the second round of the Australian Open.
In the final clash on Margaret Court Arena on the opening day of the Grand Slam, the 21-year-old Shapovalov and Sinner, 19, put on a masterclass of clean hitting and athleticism in a first career meeting between them.
"Today was just incredible tennis from both of us," Shapovalov told reporters.
"Honestly, I think Jannik is super talented. He's such an amazing player, he's a great guy, great worker. I'm sure he's going to be a very, very tough opponent in the future... I'm a really big fan of his game and how he is."
In an evenly-contested match with hardly anything to choose between the two youngsters, Sinner, who on Sunday became the youngest to win two ATP titles since Novak Djokovic in 2006, made a fast start to jump to a 3-0 lead before taking the set.
Against Sinner's immaculate hitting and robust court coverage, Shapovalov needed to raise his game and the world number 12 managed to find an extra gear and some more power behind his shots to take the next two sets.
Having played both singles and doubles almost everyday in the tuneup event the past week, Sinner's legs seemed to have run out of juice when he fell back 3-1 in the fourth set.
But the 32nd-ranked Italian found the energy to stage a fightback and level the contest at 2-2.
Before the deciding set, Shapovalov had a lengthy argument with the chair umpire after being denied a toilet break. He then received some medical attention for a shoulder niggle and returned to the court to break Sinner in the opening game.
Sinner, who used his 14-day isolation in Adelaide ahead of the Grand Slam as Rafa Nadal's hitting partner, spent whatever he had in his tank and had two opportunities to get the break back in the decider but failed to convert them.
"There's not that much difference between him and me," Sinner said, choosing his sessions against the 20-times Grand Slam singles winner as the highlight of his trip to Australia.
"He played better today during certain points, he deserved to win. It's mentally tough losing in the fifth, but it's going to be a lesson, as well."
After almost four hours, Shapovalov sealed the contest at almost 1 am in the morning with a forehand winner down the line on his second match point to set up a second-round meeting against Australian Bernard Tomic.
"Matches like this is so much fun for me to play, this is why I play the sport," Shapovalov said in his on-court interview.
"Win or lose today, it's one of the matches that I'm going to remember in my career just because ... the moment, the quality of tennis today, it was just so much fun to be out here."