This was de Minaur’s fourth consecutive trip to the round-of-16 in Melbourne, including straight-sets defeats from Sinner (2022) and Novak Djokovic (2023) before the heartbreak of losing to Andrey Rublev last year from two-sets-to-one up.
This year always loomed as his great chance to break through, given it is his first major as a top-eight seed, meaning he has been the higher-ranked player in all his matches to date.
However, that has meant a different kind of pressure.
De Minaur candidly revealed after his third-round win over Francisco Cerundolo from a set down that he had felt for the first time the expectation of carrying a nation’s hopes.
“A part of me knew that at some point there was going to be a match where pressure was going to be there, the nerves were going to be there, and the expectation was going to be there,” he said.
“I just told myself to go out there, compete. I’d rather win ugly any day over losing pretty … my next one, I’ll make sure I bring a better level.”
De Minaur did exactly that against an erratic Michelsen, racing through the first set without dropping a game then breaking him again to start the second.
It took Michelsen 41 minutes to finally get on the scoreboard – and not before committing 22 unforced errors – and he showed some fight to grab the break back as de Minaur tried to serve the second set out.
The American led the tiebreak early, but de Minaur’s on-the-run crosscourt forehand winner past his rival at the net proved decisive as he went on to secure a two-set lead.
A break in the sixth game of the third set was all the Australian star needed to complete the victory and earn another shot at world No.1 Sinner, who has won all nine of their meetings.
“The great thing about tennis is that once you step out on the court, you both start at 0-0,” de Minaur said.
“It’s a whole new day, a whole new match, and anything can happen. Sports are unpredictable. That’s exactly the mindset I’m going to have going into that match. I’m looking forward to it.
“[They are] the matches I want to be playing. It’s going to be my first match this whole tournament where I’m the underdog and don’t have all the pressure and expectation of having to win.”
Sinner alluded to playing through some sort of illness after beating Holger Rune in four sets in the heat of the day on Monday.
De Minaur said his team would analyse both their past meetings as well as Sinner’s matches this fortnight.
“Then you’ve got to play the match on face value and forget about everything that’s happened in the past,” he said.
“The only thing that I want to take from the past is the matches that I felt like I played well, and I found different areas where I could expose them.
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“We will come up with a set game plan. Obviously, a lot depends on when we play, whether it’s day or night.
“That’s two completely different matches and two different ways of playing him. I’ll get ready for a battle from the very first point until the last.”
Sinner looked vulnerable in his fourth round match earlier on Monday before overcoming 13th seed Holger Rune in four sets.
Stooped over and walking gingerly, the world No.1 looked physically broken and poised to retire.
The match level at a set a piece and on serve in the third, Sinner looked like he would struggle to even walk off the court for medical help let alone finish the match.
That he came back from his medical timeout to win was the sort of performance that could define his tilt for a second successive Australian Open victory.
After winning 6-3, 3-6, 6-3, 6-2, Sinner admitted he had been physically unwell all day.
“I was not feeling really well. I think we saw that today, I was struggling physically. I came here as late as possible,” Sinner said.
“I knew that it was going to be very, very difficult today. Playing against a tough opponent, but also playing against myself a little bit.
Jannik Sinner looked like he might have to retire midway through his match against Holger Rune, but he hung on to win.Credit: AP
“I think we saw that I was not feeling well, especially in that moment I was, you know, a bit dizzy at times.”
Reluctant to divulge details, Sinner said he did not have an injury but was dealing with a health issue.
“I talked with the doctor (during the time out) before going back on the court. I had a little checkup,” he said.
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“It was a bit helpful. I at least felt slightly better when I went back on court. I felt like the face looked a little bit better, the colour was a little bit back.”
Before leaving the court Sinner managed to hang on when Rune had him at break point on serve in that third set.
It was the moment that turned the match. Physically labouring Sinner managed to defend that break point with a stunning 37 point rally that might prove not only the best and most engaging point of the tournament, but also the most consequential. It seemed to have the dual effect of instilling the idea in Sinner that he could win and in Rune that he couldn’t.
Soon afterwards Sinner took his medical time out and was gone from the court and in doubt of even finishing the match.
On resumption, Rune should have seized his moment, but he stumbled. He soon after needed his own medical time out for a knee problem, but it coincided with the most destructive change in tactics mid-match. Rune started slicing shallow shots, taking the pace off his serve and playing drop shots. It was an approach that did not work.
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