Alexander Zverev believes US Open officials had no option but to default Novak Djokovic after he hit a linesperson with a tennis ball.
Djokovic was broken by Pablo Carreno Busta to fall 6-5 down in the first set when he hit a tennis ball towards the back of the court in frustration.
But unfortunately for the world No 1 the ball hit a lineswoman in the throat and she collapsed to the floor.
While she received treatment, Djokovic was in lengthy discussions with tournament officials and as per the rule book he was incredibly defaulted from the match.
Earlier in the day, Zverev stormed into the US Open quarter-finals after beating Alejandro Davidovich Fokina 6-2 6-2 6-1.
He then entered his press conference just as Djokovic was being defaulted from the match.
And Zverev told reporters the decision was the right but said Djokovic was ‘unlucky’.
“I mean, look, it’s unfortunate. He hit a ball, he hit a tennis ball,” he said.
“It’s very unfortunate that, you know, he hit the line judge, and especially where it hit her.
“Yeah, there is a rule in place for it. I think the supervisors and all of them are just doing their job. But, yeah, very unlucky for Novak.
“I think he’s going to be a little bit upset about it, but, yeah.
“He could have — if he would have hit it anywhere else, if it would have landed anywhere else, we are talking about a few inches, he would have been fine. So, yeah, very unlucky.”
Djokovic’s incredible exit means there will be a first time Grand Slam winner in the men’s draw.
Zverev is now among the favourite for the title and the German says the tournament has taken a major twist.
He said: “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.
“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.”