Reigning champions Canada battled back from a goal down to trounce the United States 5-1 in their world ice hockey championship opener in Russia on Friday.   Colorado Avalanche center Matt Duchene collected a goal and an assist, while Buffalo Sabres Ryan O'Reilly made two assists to extend Canada's winning series at worlds to 11 matches going back to last year's tournament when they won all of their games on the way to the title.   Last year's runners-up Russia, however, stumbled at the first hurdle as they suffered a 3-0 defeat at the hands of the Czech Republic.   In Saint Petersburg, the United States started lively with Edmonton winger Patrick Maroon opening on powerplay 4:54 into the match but clubmate Taylor Hall and Montreal winger Brendan Gallagher replied with one apiece to give Canada a 2-1 lead at first intermission.Duchene widened Canada's lead 11:37 into the second period, while Columbus Blue Jackets center Boone Jenner and Boston Bruins' Brad Marchand both scored in the third to secure the reigning champions' Group B win.

"The game was at a high level as the players showed good speed and good skills tonight," Canada head coach Bill Peters said.

"Now I'm looking forward to the next meeting with team USA in the play-offs."

In Moscow, hosts Russia were overrun in their Group A opener to the Czech Republic.

Rear back Tomas Kundratek put the Czechs ahead 14:48 into the opening period wristing the pack into the net between Columbus Blue Jackets goaltender Sergei Bobrovski's pads.

Roman Cervenka made it 2-0 with a powerplay goal 48seconds into the second, sweeping home a rebound after Bobrovski deflected Jakub Jerabek's slap shot. Michal Birner scored the third with 1:32 remaining before the final horn sending the puck into the empty net, while Dominik Furch produced 25 saves to chalk up a shutout.

- Sweden edge Latvia -

In Friday's early Group A match an overtime goal by Detroit Red Wings winger Gustav Nyquist gave 2013 champions Sweden a hard-fought 2-1 win over Latvia.

Skipper Jimmie Ericsson lifted Sweden 1-0 at 2:54 wristing the puck into the top right-handed corner from the left face-off circle.After a goalless second period Latvia's blueliner Kristaps Sotnieks levelled with 7:31 remaining in the third period on powerplay.

Nyquist scored the game-winning goal 4:06 into overtime sweeping the puck into an unguarded post on Alexander Wennberg's cross.

"It was a tricky game as Latvia played pretty well," said Sweden manager Par Marts. 

"It's really good to win this game as we have a new team with 10 guys, who are playing at their first world championship. But we need to play better and I hope we will improve our play during the tournament."Finland, winners in 2011, experienced few troubles on their way to a 6-2 win in their Group B match with Belarus.

After a goalless first period Patrik Laine scored twice and Minnesota Wild forwards Mikko Koivu and Mikael Granlund added one apiece, while Andrei Stas netted a shorthanded goal for Belarus in the second period.

Antti Pihlstrom made it 5-1 for Finland in the third period, while Granlund netted his second before Dynamo Minsk forward Alexei Kalyuzhny rounded off the scoring with nine minutes remaining.

Source :AFP