Stan Wawrinka booked comfortable passage into the quarter-finals of the Rogers Cup in Toronto with a 7-6 (7-3) 6-2 victory over Jack Sock.
Second seed Wawrinka will face Kevin Anderson in his third last-eight appearance at the tournament after overcoming a tough opening set against Sock.
"That wasn't easy, but I'm happy with the way I played in general and the win," Wawrinka said.
"It's going to be an interesting match against Anderson. It's always been difficult to beat him, but hopefully I can do that."
Anderson, the unseeded South African, progressed after clinching his third-round match against 12th seed Bernard Tomic 4-6 6-3 6-4.
Kei Nishikori, the Japanese third seed, swept aside qualifier Rajeev Ram with a 6-3 6-4 win during which he never dropped serve.
"In the first set I played really good tennis. I had some tough times, but this score shows I was dominating a little bit," said Nishikori, who now faces Grigor Dimitrov.
Source: PA
