Brad Marchand, front, celebrates with his Canadian teammates Zac Boychuk, left, Steve Stamkos, centre, and John Tavares after scoring the winning goal against Finland. ((David Josek/Associated Press))

Brad Marchand's struggles against Russia at last summer's Super Series carried over to the preliminary round of the world junior hockey championship.

But the Canadian forward stepped up when it mattered most.

The 19-year-old Boston Bruins prospect doubled his output in his team's fifth game in Pardubice, Czech Republic, scoring his second goal of the tournament — the game-winner — in a 4-2 doubling of Finland in Wednesday's quarter-finals.

"I had a real attitude problem before and I wasn't the person I had to be off the ice and mentally to be a great player on the ice," said Marchand, who was benched for last summer's final game against Russia and later told by coach Brent Sutter to clean up his act.

"I learned that and was able to fix it before coming to [the world junior selection] camp. I wanted to be a lot more of a leader."

Marchand, a native of Hammonds Plains, N.S., has avoided taking cheap penalties at the world juniors and has re-directed his energy into trying to score goals.

Marchand and linemates Claude Giroux and Kyle Turris had several
near-misses against Finland before Marchand's shot appeared to deflect off the stick of Finnish defenceman Joonas Jalvanti and into the net past goaltender Harri Sateri midway through the third period.

The Canadians improved their record to 4-1-0 and will meet the United States (4-0-0) in one semifinal Friday (2 p.m. ET). Canada beat the Americans 2-1 in a shootout in last year's semis in Leksand, Sweden.

In that game, Canadian forward Jonathan Toews — now with the NHL's Chicago Blackhawks — scored on all three of his shootout attempts to cement his country's sixth straight appearance in the gold-medal game.

Canada also defeated the U.S. 6-3 in the preliminary round of last year's tourney.

"We have a ton of pressure every time we step on the ice," Marchand said. "I don't think it changes, but I think it's going to be a lot more fun playing against the Americans because of the rivalry.

"I think it's better than Canada versus Russia now."

The U.S. shone in the preliminary round this time around, outscoring its opponents 17-8 to win Group B and earn a bye to the semifinal round.

The U.S. team also boasts the top three scorers of the tournament in James vanRiemsdyk (10 points), Colin Wilson (seven) and Jordan Schroeder (seven).

John Tavares, Steve Stamkos and Stefan Legein, into an empty net, also scored for Canada, which has won three straight gold medals at the world juniors.

"Tavares's goal on the power-play was huge in that it broke the ice for us," Canadian coach Craig Hartsburg said. "We knew he was smart and he would figure this game out, and he's one of our best players right now."

Steve Mason made 21 saves and survived a couple of ugly goals in the Canadian net to post his third win of the tournament, while defenceman Drew Doughty added two assists.

Juuso Puustinen and Jan-Mikael Juutilainen found the net for the Finns (2-3-0), who will play for fifth place after finishing sixth a year ago.

With Canada leading 2-1, Juutilainen pulled his team even when he banked a shot off Mason's right pad from behind the Canadian net at 5:42 of the third period, less than four minutes after Stamkos had given Canada the one-goal advantage.

The Finns also caught the London Knights netminder napping early in the first. Puustinen approached the Canadian blue line, looked at the corner and fired a high wrist shot the other way that soared over Mason's glove hand into the net.

Doughty set up the Stamkos marker as he entered the Finland zone from the wing and was hauled down behind the net. As the referee raised his arm to call the penalty, Stamkos banged the loose puck in on Sateri's stick side at 2:20.

Canada outshot Finland 11-6 in the first period, but couldn't get their sticks on the puck as it often wobbled and spun between Finnish legs in the goal crease.

In Wednesday's other quarter-final, Russia scored three second-period goals on the way to a 4-1 triumph over the Czech Republic and will meet Sweden (4-0-0) on Friday (10 a.m. ET).

The gold-medal game is Saturday at 2 p.m. ET in Pardubice and will be preceded by the bronze-medal contest (10 a.m. ET).

With files from the Canadian Press