Dominic Thiem believes Alexander Zverev is the toughest player to face on the ATP Tour besides Novak Djokovic and Rafael Nadal.
Thiem has a fine record against the German, beating him in eight of the ten matches they have played, including the US Open final earlier this year.
However, he still considers Zverev to be one of the favourites to win the ATP Finals next week.
“For me, personally, Sascha is the toughest opponent to play besides Roger Federer, Rafael Nadal and Novak Djokovic.
"I already said it after the US Open, both our games make things difficult for the other one. For me, it's tough to play against him because he serves and returns so well, because I always have trouble finding a good tactical plan against him.
“That’s why he is the toughest opponent, even though the last matches have gone my way. I’m already a bit scared thinking of our next matches, but I’m looking forward to it of course”.
Thiem sees another two big dark horses for the ATP Finals, though, with Russian duo Daniil Medvedev and Andrey Rublev really impressing him of late.
“In Paris, Medvedev has made his way up on the list of favourites for London,” Thiem said. “I watched the final, he played incredible in the end, made no mistakes.
“I would say besides Nadal and Djokovic, who are always the top favourites, Rublev is an extremely good candidate.
“He’s been in top form all year round and since we’ve resumed the tour after the corona break, he’s been even better."
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