Top-ranked Novak Djokovic survived a scare to beat Gilles Muller 7-5, 7-6 (3) on Wednesday in the Rogers Cup, his final event before the Rio Olympics.
The Serbian star won the event that rotates between Toronto and Montreal in 2007, 2011 and 2012.
Djokovic struggled against Muller in his first hard-court match 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.
Djokovic will face qualifier Radek Stepanek of the Czech Republic in the third round.
Third-seeded Kei Nishikori of Japan downed American Dennis Novikov 6-4, 7-5; and fourth-seeded Milos Raonic of Canada beat Taiwan’s Lu Yen-hsun 6-3, 6-3.