Paris, France: Russia's Karen Khachanov demolished fourth seed Alexander Zverev of Germany 6-1, 6-2 on Friday to power into the Paris Masters semi-finals as Novak Djokovic and Roger Federer attempted to set-up a blockbuster last-four clash.
Khachanov, the winner at last month's Kremlin Cup in Moscow, will now meet Austrian sixth seed Dominic Thiem who knocked out defending champion Jack Sock, the 16th-seeded American, 4-6, 6-4, 6-4.
Four-time Paris champion Djokovic takes on Marin Cilic in his quarter-final later on Friday, while Federer will meet Japan's Kei Nishikori.
Djokovic will replace Rafael Nadal as the world's top player on Monday after a two-year absence.
Meanwhile Federer, 37, is three wins away from his 100th career title after triumphing on home ground for his 99th in Basel last week.
World number 18 Khachanov saved two match points against John Isner in the last 16 but needed just over an hour to dispatch an out-of-sorts Zverev, who dropped his serve six times in eight games.
Khachanov, 22, shrugged off complaints from Zverev over noise coming from the Russian player's box during the match.
"When you are playing and you are losing sometimes, you just get a little bit frustrated and upset," said Khachanov, who has reached the last-four of a Masters for the second time after a semi-final run in Toronto this summer.
"Everything is fine between us and there is no problem."
Thiem continued his bid to qualify for the ATP Finals for the third consecutive year by knocking out Sock who will drop out of the world's top 100 as a result of his loss on Friday.
Thiem has won the second-most matches on the ATP Tour this year -– now 53-17 -– one behind Zverev's 54-17 record.