Alexander Zverev was "in shock" after Novak Djokovic was defaulted at the US Open on Sunday.
World number one Djokovic was stunningly disqualified after hitting a linesperson with a ball during his last-16 clash with Pablo Carreno Busta.
It means there will be a first-time grand slam champion in the men's draw, with Zverev among the contenders at Flushing Meadows.
Speaking after his 6-2 6-2 6-1 thrashing of Alejandro Davidovich Fokina, the German fifth seed was in disbelief to see Djokovic exit in such a manner.
"I don't think I have ever gotten defaulted yet in my career or in my life. No, I haven't been in a situation like that. But as I said, it's very unlucky, very unfortunate," Zverev told a news conference.
"The decision was made I think by the supervisors, and as I said, they are just doing their job. There is nothing much else I can say to that. I don't know. I mean, I don't know what to say. I'm a little bit in shock right now, to be honest."
Zverev will face either Croatian 27th seed Borna Coric or Australian Jordan Thompson in the quarter-finals.
A semi-finalist at the Australian Open this year, Zverev said he was excited by the men's draw in New York.
"There's going to be a new grand slam champion. That's all I know right now. There's no past grand slam champions left in the draw," he said.
"It's going to be one of the young guys, I think, if you count Dominic Thiem as a young guy, as well. He obviously has a chance to win, as well.
"Now it gets interesting. Now I think is the time where it gets really interesting. Yeah. I know who is where in the draw. I know who I can play. I know who the rest of the guys can play. Yeah. We'll see where we go from here."Published 07 Sep 2020, 04:44 IST