Dan Evans, the second-ranked player in the United Kingdom, defeated Karen Khachanov in straight sets to go to the Vienna Open quarterfinals.
Unseeded Evans defeated the Russian in one hour and sixteen minutes, 6-2 6-2, and will play Denis Shapovalov in the round of eight after the Canadian upset Taylor Fritz, the fourth seed, 6-1 4-6 6-3.
In other news, American Marcos Giron, who defeated Dutchman Tallon Griekspoor 6-4, 6-2 in the Austrian capital, will face British number one Cameron Norrie in the round of 16.
Stefanos Tsitsipas, the second seed, and top seed Daniil Medvedev both through to the round of 16.
In the last first-round match, world number four Medvedev defeated Nikoloz Basilashvili 6-2, 6-2, in less than an hour.
The Russian triumphed in 59 minutes and broke twice in each set without seeing a breakpoint.
In the round of 16, Medvedev will face fellow former US Open winner Dominic Thiem, who defeated American Tommy Paul in a thrilling victory on Tuesday by saving two match chances.
The Austrian Dennis Novak was defeated by the Greek Tsitsipas 7-6 (7-2) 6-2 in one hour and 28 minutes.
To get used to these new circumstances, Tsitsipas remarked, “it takes time.” “I was portraying someone whose background I didn’t know all that well. I had never previously played him.
“In the second set, I played pretty well because I could get my footing and have a nice feel for the court and the balls.
“I thought the second set was excellent. I only wish I had been able to do it in the first set, but it didn’t happen. In the first one, I had to put up a solid fight and play a strong tie-break to win.”
The following matchup features a rematch of the Cincinnati Masters final, which Coric won in September, between Tsitsipas and Croatia’s Borna Coric.
The world’s best Carlos Alcaraz defeated Botic van de Zandschulp at the Swiss Indoors to advance to his 11th quarterfinal.
The 19-year-old, who upset Jack Draper of Great Britain earlier this week, defeated the Dutchman 6-4 6-2 in Basel to advance in his pursuit of a sixth championship of the year.
Pablo Carreno Busta, a fellow Spaniard, or Dominic Stricker, a local, will square off against Alcaraz in the eighth round.