Roger Federer's bid for an 80th career title began with a 6-2 6-0 win over Peter Polansky in the second round of the Rogers Cup in Toronto.
Only Jimmy Connors (109) and Ivan Lendl (94) have won more ATP titles than Federer, a 17-time Grand Slam winner.
Elsewhere, third seed Stan Wawrinka beat French qualifier Benoit Paire 4-6 6-3 7-6 (7-2)
In the women's event, held in Montreal, home favourite Eugenie Bouchard lost to American qualifier Shelby Rogers.
The 20-year-old Canadian, who reached last month's Wimbledon final, lost 6-0 2-6 6-0.
She said: "I was feeling the pressure on the court and I was feeling kind of match rusty."
The Canadian had a conversation with her coach Nick Saviano during the first set when she appeared out of sorts.
"I want to leave the court," she said.
Saviano tried to reassure her saying: "I understand, you're doing fine, take your time in between points."
Bouchard replied: "I'm not in the match at all."
American Venus Williams beat Anastasia Pavlyuchenkova 6-1 3-6 6-2 while Caroline Wozniacki thrashed Daniela Hantuchova 6-1 6-1.
Third seed Agnieszka Radwanska, ninth seed Ana Ivanovic and 14th seed Carla Suarez Navarro also advanced.
Britain's Andy Murray will play Australian Nick Kyrgios in his first match of the hard-court season at the Rogers Cup on Wednesday.
Murray, 27, has not played since his Wimbledon title defence ended in the quarter-finals last month and was given a first-round bye in Toronto.
World number 70 Kyrgios, who beat then world number one Rafael Nadal to reach the quarter-finals at Wimbledon, secured his first victory in an ATP World Tour Masters tournament by beating Colombia's Santiago Giraldo 7-6 (7-3) 7-5.