MONTREAL (AFP) - Croatian Ivan Dodig stunned second seed Rafael Nadal Wednesday, beating the Spaniard in his opening match at the Montreal Masters 1-6, 7-6 (7/5), 7-6 (7/5). After dropping the first set, the 41st-ranked Dodig worked to turn things around and completed his comeback after just over three hours with the aid of 19 aces and three breaks of Nadal's serve. At 5-5 in the third-set tiebreaker, Dodig belted a 135 mph ace past Nadal. He followed up with a backhand that Nadal could do nothing with. That was exactly when Dodig began to dig in, his serve getting him out of trouble on repeated occasions. Nadal, a two-time Canada champion in 2005 and 2008, was unable to serve out the win, as Dodig took it into a third-set tiebreaker and came back from 0-2 down. The Croatian has had a breakthrough year, winning his first ATP World Tour title at home in Zagreb and climbing into the top 50 from 88th at the start of the season. Nadal's loss was his ninth this season against 51 wins. He had not played since losing the Wimbledon final to Novak Djokovic, who displaced him as world number one. Novak Djokovic made his first ATP match as the world number one a victory on Wednesday, shaking off a slow start to beat Nikolay Davydenko 7-5, 6-1 at the Montreal Masters. The victory in just over 90 minutes wasn't smooth sailing for the Serbian, who raised his level to rally from 1-4 down in the opening set against the former top-five regular from Russia. Djokovic has now won 49 of the 50 matches he has played this season. He rose to number one in the world in the wake of his Wimbledon triumph, ending Rafael Nadal's 56-week reign atop the rankings. In Montreal, Djokovic is vying for a repeat of the title he claimed in 2007. He has never lost before the quarterfinals in Canada. Djokovic broke Davydenko seven times in a match originally scheduled for Tuesday but pushed back a day by rain. Davydenko, now ranked 30th, has lost four of his six career matches against Djokovic. Third seed Roger Federer began his hardcourt run to the US Open with a clinical 7-5, 6-3 defeat of Canadian wild card Vasek Pospisil. The Swiss, playing his first ATP match since his Wimbledon quarterfinal loss to Jo-Wilfried Tsonga, set up a re-match with the Frenchman, who advanced with a 6-3, 7-6 (7/1) victory over Australian Bernard Tomic. Federer said he was looking forward to facing Tsonga again, but warned the contest is wide open. "It depends on the conditions, we might play at night or during the day. At Wimbledon it was really a matter of our serves and forehands. It was a matter of a couple of points." Tsonga said he's taking nothing for granted as he meets his rival for the second time in six weeks. "He's still the best player ever for me and it's still tough to play against him," said Tsonga. "The wins I had in the past, they will help me, of course," added Tsonga, who won a Montreal quarter-final two years ago against Federer. "But I've lost against him (four) times." Federer is vying for a third Canadian title, after winning in 2004 and 2006. He said it was always a relief to get past a local favourite such as Pospisil. "It was tough conditions, it was quick and he had good crowd support," Federer said. "He had nothing to lose. It was a tricky match for me to play today." Stanislas Wawrinka completed a Swiss double, defeating American Michael Russell 6-3, 6-2 in just over an hour. "I played a good match, saved one or two breakpoints," Wawrinka said. "I was able to do that and play aggressive. I'm happy with that match." French fifth seed Gael Monfils advanced, defeating Alex Bogomolov 6-2, 7-6 (7/5) and 10th-seeded Richard Gasquet earned another win for France, defeating Brazilian Thomaz Bellucci 6-1, 6-4. Seventh-seeded Czech Tomas Berdych advanced, rallying for a 4-6, 6-2, 6-3 victory over Alexandr Dolgopolov, while eighth-seeded Nicolas Almagro beat Sergiy Stakhovsky 6-2, 7-6 (7/5).