Novak Djokovic's quest for a record Grand Slam title continued in dramatic circumstances after fifth seed Lorenzo Musetti quit their Australian Open quarter-final match with an injury after taking a two-set lead at Melbourne Park on Wednesday.
Musetti's retirement when leading 6-4 6-3 1-3 meant Djokovic pulled off a great escape at his most successful hunting ground, with the 10-times champion's bid for a standalone 25th major to break the tie with Margaret Court still alive.
The 38-year-old Serb returned to action after an extended break following fourth-round opponent Jakub Mensik's walkover on Sunday, and his freshness showed during a sharp start where he brought plenty of variety and grabbed an early break.
The sport we all love can be brutal sometimes... 💔
— #AusOpen (@AustralianOpen) January 28, 2026
WIshing you a speedy recovery, Lorenzo 🙌@wwos @espn @tntsports @wowowtennis #AO26 pic.twitter.com/bC5wLyLrxo
But some loose points thereafter allowed Musetti to level at 2-2 and the Italian then surged past Djokovic for the first time in the contest with an overhead shot before comfortably wrapping up the opening set on serve.
Some fiery winners from both flanks helped Musetti break in the opening game of the next set, and though the 23-year-old let the advantage slip immediately, he edged in front again and soon doubled his lead in the match to leave Djokovic on the ropes.
Djokovic soldiered on following treatment for a foot blister and went 2-1 up with a break in the third, when it was Musetti's turn to call the trainer to the court for what appeared like a right thigh issue.
Musetti looked to manage the problem and play on but he was far from 100% and threw in the towel to gasps from the crowd on Rod Laver Arena, handing Djokovic his 103rd match win at the tournament to eclipse Roger Federer's mark.
The Serb said: "I don't know what to say except that I feel really sorry for him.
"He was the far better player, I was on my way home.
"It happened to me a few times but being in the quarters of a slam, two sets to love up, in full control, so unfortunate.
"I wish him a speedy recovery and he should have been the winner today no doubt."
Jannik Sinner, unstoppable, unplayable, and into the #AO26 semis 👏💯@wwos @espn @tntsports @wowowtennis #AO26 pic.twitter.com/vmYJrqRul7
— #AusOpen (@AustralianOpen) January 28, 2026
Djokovic next faces Jannik Sinner after the Italian's straight-sets win over Ben Shelton.
Sinner's dramas of the third round, when he was in serious trouble in the heat against Eliot Spizzirri, now seem a distant memory, with the two-time defending champion brushing aside big-serving Shelton 6-3 6-4 6-4.
It was his third win against the American in the last five slams, and now, for the third time in the last four majors, he finds Djokovic waiting in the semi-finals.
"It’s very tough to play against Ben," said Sinner.
"Huge serve and I feel like he’s improving so much year after year. Very happy about today’s performance. I felt like I returned great today."
On facing Djokovic, the 24-year-old added: "These are moments why you practise, you wake up in the morning and you look forward to play hopefully a good match. We are still lucky to have Novak here playing incredible tennis with his age. Hopefully it’s going to be a great battle."
Sinner’s strengths will, of course, come as no surprise to Djokovic, who has not won a set against the Italian since a meeting here two years ago, losing to him at the French Open and Wimbledon last year.
Musetti said: "We have done all the exams and tests before starting the season to see and to try and prevent these kind of injuries, and then they say nothing came out, so I honestly have no words to describe how I'm feeling right now and how tough is for me this injury in this moment.
"Honestly, I never imagined the feeling of leading two sets to zero against Novak and playing like that and have the lead of the match like that and be forced to retire.
"Of course, it’s really painful."
