It’s point by point, game by game as Alex de Minaur refuses to look too far ahead after gatecrashing the quarter-finals of a grand slam for the first time.

De Minaur broke Vasek Pospisil’s spirit in a 7-6 (8-6) 6-3 6-2 fourth-round triumph on Tuesday to join John Millman as only the second Australian man in more than a decade to reach the US Open’s last eight.

It was one-way traffic after de Minaur, the tournament’s 21st seed, rallied to save four straight set points in the opening tiebreaker to see off the big-hitting Canadian in two hours and 17 minutes.

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“I was thinking to myself that I didn’t really deserve to be in that position right there. I thought I got a little bit unlucky to go down 6-2 in the tiebreak because I didn’t think I played a bad tiebreak,” de Minaur said.

“Mainly I just tried to stick and stay in the moment.

“I knew if I could jag that first point on his serve, then maybe I would have two points on my serve and hopefully he would feel the pressure a little bit.

“But I actually ended up playing some great tennis, putting some very good deep returns and starting to dictate.

“I’m very happy I got that first set, and the momentum definitely changed after that.”

Former world No.1 Lleyton Hewitt was a fixture in the men’s quarter-finals in New York from 2000 to 2006, but it’s been slim pickings since for Australian men.

It took an earth-moving fourth-round victory for Millman over Roger Federer two years ago to break the drought.

But, now that he’s there, de Minaur has a golden opportunity to progress even further in a draw depleted by Novak Djokovic’s dramatic disqualification on Monday after Federer and defending champion Rafael Nadal didn’t even start.

De Minaur will play Austrian second seed Dominic Thiem, who stormed into his second career US Open quarter-final with a routine straight-sets success over Canadian Felix Auger-Aliassime.

For now, that is de Minaur’s focus.

“Nothing changes.” he said.

“I’ve just got my match ahead of me and I think it (Djokovic’s elimination) affects more the people on that side of the draw, to be honest.

“It’s still a long way away to get to that final. So I’m going to stick with my quarter-finals for the time being.”

But with Djokovic disqualified after striking a line judge in the throat with a ball, Federer, Nadal and 2016 winner Stan Wawrinka not at Flushing Meadows and Andy Murray suffering an early exit, a first-time grand slam champion is guaranteed this week.

“Look, I’m obviously very happy. At the end of the day, this is where I want to be and this is where I truly believe I belong – second weeks of slams and going deep,” de Minaur said.

“I’m happy I’m finally at this stage.

“But nothing changes. Everything stays the same. Now I’ve got just another match awaiting for me.”

-with AAP