TORONTO - Canadian Milos Raonic downed Yen-Hsun Lu of Chinese Taipei 6-3, 6-3 on Wednesday evening in the second round of the Rogers Cup.

Raonic, from nearby Thornhill, Ont., will face American Jared Donaldson in the third round of the tournament.

Raonic relied on his booming serve, especially in the second set, and finished off the match with his eighth ace which Lu deflected high and wide.

Raonic had some trouble with his volleys and returns in the opening of the first set, so he started using his serve more heavily.

That shift in strategy gave him an 85 per cent serving efficiency in the first set and helped him pull away from Lu after they were tied 3-3.

In the second set, Raonic's success with the serve allowed him to be more aggressive, moving to the net more often and forcing Lu to make errors.

Raonic found his hometown crowd at York University's Aviva Centre to be somewhat of a distraction in the second set. He repeatedly complained to the chair umpire about conversations floating down to the court while he was serving or people walking in the aisles during the match.

Despite those distractions, a smile played across his face when some fans shouted "Another win for Milos!" referencing an episode of the 1990s sitcom Seinfeld.

He responded to the playful call from the centre-court crowd with his seventh ace of the night to take a 5-2 lead in the second set.

Earlier Wednesday, world No. 1 Novak Djokovic survived a scare from Gilles Muller and held on for a 7-5, 7-6 (3) win. Although he seemed tired and sometimes frustrated in the heat, Djokovic insisted that it was worth playing in Canada despite his busy ATP schedule.

"I actually think that Toronto is a great way for me to prepare for the Olympic Games and what's coming up after that," said Djokovic, who noted that since he was upset in the third round at Wimbledon he had extra time off. "But also, you know, I enjoy my time in this tournament that I always love playing.

"I enjoy Canada, both cities, Toronto and Montreal, and the past results in history shows that I have a good time on Canadian soil, so I try to get the best out of it."

Although many top players have backed out of playing at the Rio Games - including Roger Federer and Raonic - because of the potential risk of being exposed to the Zika virus or lingering injuries, Djokovic confirmed on Wednesday that he was committed to playing for Serbia at the international event.

Djokovic struggled against Muller on the hard court - his first match on the surface since March - both with his serves and his short game. Ultimately, unforced errors were Muller's undoing, with both sets easily in reach of the unseeded player from Luxembourg.

"Gilles Muller is a very difficult player to play against in quick conditions," said Djokovic. "He takes away the time of the opponent. He serves and volleys second serve a lot, as well, which he's one of the rare guys that does that.

"He likes to play quick, and I think the warm day like today played a lot in his favour."

Also in second-round play, Radek Stepanek of the Czech Republic downed Peter Polansky of nearby Thornhill, Ont., 7-6 (5), 6-4. Australia's Bernard Tomic defeated Toronto's Steven Diez 6-3, 7-6 (4).

No. 2 seed Stan Wawrinka needed two tiebreaks to beat Mikhail Youzhny 7-6 (3), 7-6 (8), third seed Kei Nishikori downed Dennis Novikov 6-4, 7-5 and fifth seed Tomas Berdych dispatched Borna Coric 4-6, 6-1, 6-4.

Ryan Harrison upset ninth seeded John Isner 7-6 (3), 6-7 (4), 6-4, Rajeev Ram beat Lucas Pouille 6-4, 7-6 and Jack Sock cruised past Donald Young 6-4, 6-3.