Dominic Thiem says Andrey Rublev is one of the best five players in the world right now ahead of their Vienna Open clash.
No one has won more titles in 2020 than Rublev, who has four to his name, and he has broken into the world's top ten for the first time in his career.
Thiem will face the Russian in the last eight of Vienna on Friday, and he's obviously well aware of the threat Rublev poses.
"[Rublev is one of] my favourite people and my favourite training partner on the tour," Thiem said.
"He just moved into the top ten last week and I would say that the way he is currently playing he is one of the five best players in the world.
"He plays every ball at top speed. It will be an incredibly difficult task."
Thiem defeated Cristian Garin 6-3, 6-2 on Thursday to earn his shot at Rublev, and he says it was a much more difficult match than it appeared.
"It was a really good game, very solid from start to finish," he said.
"The first game was also anything but bad, but against an opponent who ranked much worse than he played.
"I actually did very few stupid things today, a lot of first serves, returned well."
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