James van Riemsdyk and Drayson Bowman each scored a pair of goals to lead the U.S. to a 8-2 win over Germany to open the world junior hockey championship Friday.
Bowman is a forward with the Western Hockey League's Spokane Chiefs and was named player of the game for the U.S.
Van Riemsdyk, the second overall pick in the 2007 NHL entry draft by Philadelphia, is in his sophomore year at the University of New Hampshire.
Minnesota's Jordan Schroeder had a goal and two assists in the victory. Colin Wilson of Boston University contributed a goal and an assist.
Michigan's Matt Rust and Bowman's Chiefs teammate Tyler Johnson also scored. Spokane forward Mitch Wahl had two assists.
The Americans peppered the German net with 46 shots. Timo Pielmeier, who plays for the Quebec Major Junior Hockey League's Shawinigan Cataractes, gave up five goals on 27 shots in the first two periods.
Pielmeier was replaced by Philipp Grubauer of the Belleville Bulls to start the third. Grubauer allowed two goals on 19 shots.
Thomas McCollum of the Ontario Hockey League's Guelph Storm stopped 16 of 18 in net for the U.S.
Toni Ritter and Patrick Pohl scored for the Germans, who earned promotion to this tournament by winning one of two world 'B' junior championship earlier this year.
The Americans are in a pool with Canada, the Czech Republic, Kazakhstan and Germany. They face the Czechs on Sunday.
The team with the best record at the end of the preliminary round earns a bye to the semifinals. The runner-up and third-place teams will play a quarter-final.
Canada 8, Czech Republic 1
John Tavares of the Oshawa Generals paced Canada to an 8-1 win over the Czech Republic with two goals and an assist Friday at the world junior hockey championship.
Angelo Esposito of the Montreal Junior, Windsor Spitfires defenceman Ryan Ellis, Medicine Hat Tigers forward Tyler Ennis, Chris DiDomenico of the Saint John Sea Dogs, Zach Boychuk of the Lethbridge Hurricanes and Niagara IceDogs defenceman Alex Pietrangelo also scored for the defending champions.
The announced crowd of 19,622 at Scotiabank Place was a world junior hockey championship attendance record for a single game.
Jordan Eberle and Boychuk contributed a pair of assists apiece.
Dustin Tokarski's shutout bid ended with two minutes remaining when Jan Kana scored on the Spokane Chiefs goaltender. Tokarski made 21 saves for the win.
Canada, winner of four straight world junior titles, faces Kazakhstan on Sunday. The U.S. beat Germany 8-2 earlier in another Pool A game.
Russia downed Latvia 4-1 and Sweden beat Finland 3-1 in Pool B.
The team with the best record in each pool at the end of the preliminary round earns a bye to the semifinals. The runners-up meet the third seed from the opposite pool in the quarter-final.
Tavares is a possible No. 1 pick in the 2009 NHL entry draft and he displayed his considerable puckhandling skills in the tournament-opener for Canada.
He broke the first-period tension for his teammates by scoring a power-play goal with just four seconds remaining. Tavares scored another early in the second to jump start Canada's victory.
Canada scored four goals in the second period and chased Czech goaltender Tomas Vosvrda from his net. He gave up five goals on 22 shots and was replaced by Dominik Furch after Ennis's goal at 13:33 of the second period.
DiDomenico, Boychuk and Pietrangelo scored in the third to turn the game into a route.
Russia 4, Latvia 1
Russia has found the win column at the world junior hockey championship.
Pavel Chernov had a goal and an assist to lead the Russians to a 4-1 win over Latvia in the tournament's opening game on Friday.
"It wasn't a great game on our part, but it was a solid win in the first game," Russia's Nikita Filatov told the IIHF website. "So this was okay. Latvia in an opening game is not easy."
Vyacheslav Voinov, Maxim Goncharov and Dmitri Klopov also scored for Russia.
Janis Ozololins replied with Latvia's lone goal.