Toronto: Ivan Dodig made a triumphant return from injury with a 6-4, 6-7 (4), 6-3 upset victory over 10th seeded American John Isner in the opening round of Rogers Cup on Monday after the Croat missed nearly three months with a broken rib.
Dodig, back on court for the first time since retiring in the opening round of the French Open, showed no sign of rust as he consigned Isner to a second consecutive first round loss.
Twice a winner this season, Isner got his North American hard court campaign off to a confident start by picking up a ninth career title two weeks ago in Atlanta.
However, the big-serving American has been misfiring ever since, suffering an early exit to compatriot Steve Johnson last week in Washington, followed by another shock loss in Toronto.
"I was really happy to play again and to beat Isner is a great win for me for sure," said Dodig, who has watched his world ranking dip to number 62.
"I hope I can continue. I'm just really happy to be again on the court this is most important to me.
"He is the guy who can beat anybody and a great player for many years. Today was tough match for both of us and I was a little bit more lucky this time."
Isner was not the only big name to falter and he was joined in the departure lounge by 14th seeded Spaniard Roberto Bautista Agut, who was dispatched 7-6 (7), 6-3 by compatriot Feliciano Lopez.
The tournament got off to a stuttering start with morning and afternoon matches interrupted by rain but despite the stormy weather, the two other seeds in action Day One, Marin Cilic and Jo-Wilfried Tsonga, progressed into the second round.
Croatian 15th seed Cilic, another two-time winner on the ATP Tour this season, continued his domination of Uzbekistan's Denis Istomin taking a 6-2, 4-6, 7-5 decision to improve his record to 5-1.
In an all-French battle 13th seeded Tsonga survived an early challenge from Eduard Roger-Vasselin before easing to a 7-6 (3), 6-1 win.
"It's always difficult when you didn't play for a few weeks but it was my choice and I practiced a lot during those weeks," said Tsonga, after playing his first match since a fourth round loss to Novak Djokovic at Wimbledon.
"Of course, you know, when you come on the court for the first time again, you want to be good. You want to see if your practice was good or not.
"So I was a little bit more stressful but in the second set I played well. So it's good."
Australian former world number one Lleyton Hewitt, twice a winner this season, never found his footing on the Canadian hard court falling 6-1, 6-2 to Frenchman Julien Benneteau, playing his 242nd ATP Tour event and still searching for a first title.
The Canadian stop is considered one of the key warmup events ahead of the US Open starting later this month and has again attracted a top flight field that includes world number one Djokovic and 17-time grand slam winner Roger Federer.
There is an added buzz surrounding this year's event in the hockey-mad country after local players Milos Raonic and Vasek Pospisil clashed at the Citi Open in Washington Sunday, facing off in a first ever all-Canadian ATP Tour final.