Jannik Sinner was far from his best but found a way to come out on top in the key moments as he reached the quarter-finals of the Australian Open with a 6-4 7-5 6-3 win over Karen Khachanov on Sunday.

The Italian fourth seed, widely tipped as a title contender after a scorching finish to last season, had stormed into the fourth round without really being tested but knew he had been in a match on a blustery Margaret Court Arena.

“Usually when we play it’s a tough match, he’s an incredible player, I tried to stay focused, mentally and physically,” Sinner said.

“Every match has its own story. Today I won so I’m very happy. We have quite a similar game style, so it’s a kind of ping-pong. I tried to mix it up a bit today.”

Khachanov, a Melbourne semi-finalist in 2023, should have been the first player to take a set off Sinner this year as the Italian struggled with his serve early in the match.

The Russian 15th seed earned 10 break points over the first two sets but, partly through his own mistakes and partly through fine clutch serving from Sinner, failed to convert all but one.

Sinner, by contrast, clinically drove home his advantage on all three of the break chances he carved out and went two sets up with his eighth ace after nearly two hours on court.

The 22-year-old was unable to relax, however, knowing that Khachanov had come from two sets down to beat him in their only previous Grand Slam meeting at the 2020 U.S. Open.

Sinner is a different player three years on and looked comfortable going toe-to-toe with Khachanov in the power stakes, while also trying out the drop shots that new coach Darren Cahill has brought to his game.

Khachanov did manage to save three break points in the third set but when he gave up the fourth with a wild forehand to go 4-3 down, the writing was on the wall for the Russian’s campaign.

Sinner played his best tennis in the final two games, adding a couple more winners to his final tally of 46 and moving onto a meeting with Andrey Rublev or Alex de Minaur in his second visit to the Melbourne Park quarter-finals.