Alexander Zverev is one of only three men to defeat Novak Djokovic since the start of Wimbledon.
The 21-year-old German toppled Roger Federer and Djokovic in succession to capture the most prestigious title of his career at the ATP Finals in London.
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Zverev punctuated a declarative performane with a determined vow to the game's elite: We're coming.
The fourth-ranked Zverev joined 20-year-old Stefanos Tsitsipas, who upset Djokovic and Zverev en route to the Toronto final in August, and Karen Khachanov, who toppled Dominic Thiem, Zverev and Djokovic in succession to win the Paris Masters as one of three men to defeat the 14-time Grand Slam champion since Wimbledon began.
Zverev, who led the ATP with 58 victories on the season, said the NextGen stars are announcing their arrival as major contenders.
"Obviously us young guys, we're coming through," Zverev told the media in London. "Khachanov winning the Masters in Paris was a big thing. I was very happy for him, as well. I wasn't happy that he beat me, but I was happy for the victory that he had because I'm quite good friends with him.
"The victory for Tsitsipas in Toronto, I felt like Novak wasn't playing his best there, but obviously all the credit to Tsitsipas. You have to beat someone like Novak because he's not going to give you the match. He's done just that."
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