Additional reporting from Kamakshi Tandon.
Zverev is into the first Grand Slam quarterfinal of his career after defeating Karen Khachanov in five sets. It was the third match in a row that the German was forced to come back from being down two sets to one. At this point, he's had all the five-set experience he wants.
"It's not about learning anymore. It's about trying to find a way to win," he said. "I'm very happy about being in the quarterfinals here the hard way, going the long distance every single time and showing myself, showing everybody, that I can play for as long as I need to."
Still, Zverev's experience might have helped him against his slightly older but lower-ranked opponent.
"Sometimes you've got to be emotional. Sometimes you've got to be quiet. Sometimes you've got to get the crowd involved. Sometimes you don't," he said. "In this match I had to get myself going and the crowd a little bit, so it gets a little louder. You know, I successfully did."
Zverev had previously come under scrutiny for his relative underperformance at Grand Slams—especially considering the fact that he has won three Masters titles.
Having rectified that, he now wants more, saying, "I'm happy. But this is [just] the quarterfinal."
Thiem, on the other hand, is coming off of an incredibly impressive fourth-round win, as the Austrian beat Kei Nishikori 6-2, 6-0, 5-7, 6-4.
Zverev won 6-4, 6-4 when the two met in the final in Madrid just a few weeks ago, but the Austrian is still 4-2 in their head-to-head history. He also won when the two of them met in the round of 32 at the 2016 French Open.
WATCH—Championship point from Zverev's win over Thiem in Madrid:
“Well, I think that's the matchup most of the fans in Germany and Austria were hoping for when they saw the draw. So it's going to be a very nice match again,” the world No. 7 said about Zverev. “And he’s going to be great. He's [an] amazing player. I mean, probably now the third- best after Rafa [Nadal] and Roger [Federer]. So it's going to be an amazing challenge for me."
Thiem, who has reached the semis at the French Open twice, says that he is on top of the ball this week.
“Honestly, I'm happy with all of my game. There is no point where I would say that it's not working,” Thiem said. “I’m moving well, feeling physically very good. Groundstrokes are great. Serve, especially today, I was serving great. I just tried to keep it up and keep that level.”
Now almost 25, Thiem wants to make a big move, noting, “I’m not that young anymore.”
But he knows his 21-year-old opponent is also looking for a run, and will be more confident because of his victory at Madrid.
“Completely different conditions, but still, it's going to be a very tough match against him," said Thiem. "He's going to be pumped. It's [Zverev’s] first quarterfinals [at the Grand Slam].
"So I hope I'm a little bit more experienced.”
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