The 38-year-old was dominant on Arthur Ashe Stadium, dispatching the unseeded German inside two hours to set up a tough-looking clash with American crowd favourite Taylor Fritz.
Flushing Meadows has not seen a player as old as Djokovic reach this stage of the competition since Jimmy Connors’ run to the semi-finals in 1991, and when asked if winning the title would be the greatest achievement of his career to date, the Serbian replied: “It could be.
“Still a very long way [to go]. In the last couple of years, I learned to take one match at a time. And yes, of course, I’m dreaming about winning another Slam, and it would be amazing if I do it here.
“But I can’t allow myself to go that far with my thinking, because I just need to focus on what needs to be done to win the next match, next challenge.
“The last Grand Slam I won was here actually two years ago. So it would be a nice kind of journey in the last couple of years – to kind of close the circle here again would be great.”
‘Of course, I’m dreaming about winning another slam’ – Djokovic optimistic as he moves into quarters
Video credit: SNTV
Despite taking on a reduced schedule this campaign – only playing one exhibition between the French Open, Wimbledon and US Open – Djokovic has gone deep in each of the majors, reaching the semi-finals of the first three.
Per the BBC, with his win over Struff, Djokovic became the oldest player in the Open era to reach the quarter-finals at all four Grand Slam events in a single season.
He was in rampant form to dispatch Struff on Sunday, conceding just a single break to take a 6-3 6-3 6-2 victory.
There were some fears for Djokovic when his neck and right forearm were tended to by physios, but he showed no signs of letting injury hamper his performance, rattling off 12 aces and 33 winners; his spot in the final eight never looked in doubt.
“I think I had a great serving performance in the last round and also tonight,” Djokovic said.
“I just saw the stats, I out-served one of the guys that had the most aces during the tournament this year, so that’s a great stat. Obviously that helps make my life easier on the court.”
Djokovic holds a 10-0 record over his quarter-final opponent Fritz, but he is expecting an “uncomfortable” clash against the No. 4-seeded American.
“I expect players that never won against me to come out on the court and try something different, try to make me feel maybe uncomfortable and play more aggressive,” Djokovic said.
“I don’t think there’s going to be any major changes with Taylor, because obviously you stick to the kind of game plan that got you to the quarters, and you know what your strengths are.
“I think over the years he has improved with his movement a lot. His backhand is also very solid, very flat. For a big guy, he moves really well. I think it’s quite underestimated how well he’s moving, particularly in the last couple of years, which was something that was probably missing in his game from before.
“That’s what got him to [last year’s] final and several semi-finals of Grand Slams. He’s knocking on that door.”
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