"Obviously Rafa, Novak and Roger have had a great rivalry for many, many years, it started from a young age so hopefully we’re the ones… maybe some of the other guys as well, [Denis] Shapovalov is playing great tennis", said Zverev.
"Some of the young guys are not here yet but I’m sure they will arrive here very soon. There’s a very strong group of guys. We’ll see how it goes, three years ago when I had my breakthrough season I made it here first time, I didn’t expect to make it that quick.
"I think if you look at Daniil the year he had was amazing but was also kind of a surprise maybe to a lot of people. We’ll see results that are unexpected but normal, we’ll see other guys starting to win big tournaments.
"I think the next two years are very exciting. The other guys are still there, they’re playing the best tennis in the world, they’re still better than us, that’s a fact, they’re the ones winning the big tournaments.
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"But I think the younger guys are improving quite quickly."
Zverev is preparing for the ATP Finals, which he won last year with victory over Djokovic in the final.