“Me personally, I thought there were some ridiculous points in the end of the tiebreak,” Zverev said after sealing his place as the group winner and reaching Saturday’s semi-final.

“Really, I mean, this is the thing about Carlos. He might not be playing, like, at his best, even though I thought he played phenomenal today. I'm just saying generally sometimes he's not playing at his best.

“All of a sudden in the most important moments, he turns into a different person. All of a sudden you can't hit a winner against him. All of a sudden he hits every single passing shot on the line.

“Like, you could put a coin there and he would hit it. That's what makes him one of the best players in the world.”

While the world No. 2 was full of praise for his opponent, Alcaraz completely disagreed. The 21-year-old was asked to explain how he stepped it up in the high-pressure moments after being informed of what Zverev said.

And he had a message for the German. “I'm happy to hear it because I left the court thinking about the opposite thing, that in difficult moments I'm not showing the best tennis. Thank you, Sascha, if you see this in the video,” he smiled.

“But yeah, I mean, I've played a lot of important moments during the season in a lot of matches. But I feel like, for example today, yeah, the tiebreak I played really good points when I was 5-2 down, for example.

“At the same time second set when I had my chances 15-40, first out, 30-40, second ball out. In those moments I feel like I'm not ready to put in a battle.”

It’s something Alcaraz wants to work on as he added: “Some matches I have not, let's say, I'm not constant in those moments. Probably in some matches I've played unbelievable points, unbelievable games.

“But in some matches when the chances is there, I miss a lot. I have to work on it. I have to work to be more consistency. Let's see.

“But yeah, I'm happy to know that I have to work on it, that I have to improve it. Let's see next year.”

Zverev will now face Taylor Fritz in the semi-final, offering him another opportunity to get some revenge after losing their last three.