Vancouver's Vasek Pospisil bounced back from a first set loss to advance to the second round of the Western & Southern Open, defeating Radek Stepanek of the Czech Republic 5-7, 6-1, 7-6 (4) on Tuesday.
It was Pospisil's second career victory over Stepanek, whom he beat last year at the Rogers Cup event in Montreal in straight sets.
Pospisil moves on to face second seed Roger Federer in the next round.
Both Eugenie Bouchard of Montreal and Milos Raonic of Thornhill, Ont. had opening round byes.
In other men's play, Marin Cilic advanced to the second round with a 6-3, 6-4 win over Feliciano Lopez, while qualifier James Ward, ranked 148th, upset No. 32 Guillermo Garcia-Lopez, 6-2, 3-6, 6-1.
On the women's side, Lucie Safarova outlasted Venus Williams 6-7 (2), 6-3, 6-4.
Suarez Navarro also needed three sets to get past Tsvetana Pironkova 6-3, 1-6, 6-2.
Meanwhile, defending champion Victoria Azarenka withdrew because of a right knee injury, the WTA said. Azarenka withdrew after practising early Tuesday and was replaced in the draw by Mona Barthel.
Azarenka injured her knee in her first-round win at Wimbledon and played in two tournaments after the grass-court major. She hopes to be ready for the U.S. Open, which starts Aug. 25.
"I'm going to get more treatment and get more work done and should be good for the U.S. Open," Azarenka said in a release. "I feel strongly that it's the best for me at this moment."
Rafa Nadal, meanwhile, will decide by the end of this week whether he is fit enough to defend his U.S. Open title after suffering a right wrist injury that ruled him out of two tune-up events, the Spaniard's spokesman said on Tuesday.
"He went for a check (up) today in Barcelona and (the) imagery looks as predicted. He will practice in the next days and decide on Friday or Saturday," his spokesman said ahead of the U.S grand slam which starts later this month.
The 28-year-old Majorcan left-hander sustained the injury during practice last month and has been training with a cast on his right wrist.
Nadal was forced to withdraw from last week's Rogers Cup in Toronto and this week's Cincinnati Open, putting in doubt his participation at the year's final grand slam at Flushing Meadows in New York starting on Aug. 25.
Last week the world number two posted a picture of himself working on court with his uncle and coach Toni in which a black wrist support was clearly visible.
"Making the most of these days to continue training, always with desire and optimism," Nadal wrote.
Files from Reuters were used in this report