Canadian fifth seed Denis Shapovalov was a major casualty in the second round of the National Bank Open in Toronto after a straight-sets defeat to Francis Tiafoe.
Unseeded American Tiafoe swept aside the local 6-1 6-4 in one hour and 15 minutes to secure his third-round spot against 11th seed Gael Monfils who beat John Millman 3-6 6-3 6-4.
Tiafoe was only in the Toronto main draw as a lucky loser after being defeated in qualifying by Emil Ruusuvuori but he hit 14 winners in an emphatic display.
World number 10 Shapovalov was unable to generate any break points while Tiafoe reeled off five games in a row, with two breaks, to win the first set.
The Canadian continued to struggle with his serve in windy conditions, as the American world number 52 won 88 per cent (23/26) of points on his first serve.
Another local hope, ninth seed Felix Auger-Aliassime, also was eliminated, going down 7-5 6-4 to Serbian Dusan Lajovic.
The Canadian hit six aces to Lajovic's none, but was undone by unforced errors at key times, with a double fault gifting the Serbian a 6-5 lead in the opening set.
Australian 12th seed Alex de Minaur also bowed out after a one-sided 6-1 6-1 defeat to Georgian world number 42 Nicolas Basilashvili.
Basilashvili sent down 6-2 aces and converted five of his six break points generated in an impressive display.
Australian qualifier Jack Duckworth booked a third-round ticket against top seed Daniil Medvedev after upsetting 16th seed Jannik Sinner, who won last week's Citi Open.
Fourth seed Andrey Rublev won through with a 7-6 (7-4) 6-3 victory over Fabio Fognini, while seventh seed Hubert Hurkacz progressed with a walkover after Kei Nishikori retired with a shoulder injury.
Eighth seed Diego Schwartzman beat Benoit Paire 7-5 6-1, while 10th seed Roberto Bautista Agut handled Tommy Paul 6-3 6-4.
John Isner knocked out 13th seed Cristian Garin in three sets, while Lloyd Harris beat Feliciano Lopez in two and Karen Khachanov defeated compatriot Aslan Karatsev 7-6 (9-7) 6-4 to secure a third-round meeting with third seed Stefanos Tsitsipas.
Tsitsipas pledged to help those affected by the fires in his homeland in his post-match press conference on Tuesday.
“My heart is with all the people of Greece,” Tsitsipas said. “I come from the south suburbs of Athens. When I was there a few days ago, I could see the fires from the south. Huge, giant clouds, smoke, which you could see from far, far away. It wasn't very nice. Even at the beach that day when I went to swim, you could see all the debris from the smoke and from the fires in the sea.”