Canada will have to play for bronze at the world under-18 hockey championship.

David Kase scored at 6:17 of overtime to give the Czech Republic a 4-3 semifinal win over Canada on Saturday in Lapeenranta, Finland. Kase converted a turnover in the Canadian zone to move the Czechs into the tournament final against the United States on Sunday.

The Americans advanced with a 4-1 semifinal victory over Sweden.

Canada, the defending champion who erased an early 3-0 deficit, will play the Swedes for the bronze medal on Sunday.

"It's not easy," Canadian head coach Kevin Dineen said. "You just don't walk by this, you feel the sting of it and understand it's going to be a tough game for both teams.

"But it has to be something that we understand about playing for your country. There's opportunity to finish strong and we've got to come out and show some respect for our country by playing extremely hard."

The Czechs dominated overtime, outshooting Canada 5-1 in the extra frame and forcing goalie Mason McDonald to come up big. But the Canadians had a glorious chance to earn the victory when they went on the power play after David Pastrnak was called for hooking Travis Konecny at 2:07, but couldn't come up with the winner.

Dineen said that was indeed a lost opportunity for his squad.

"Absolutely," he said. "They were able to clear two pucks out and unfortunately for us we didn't have a net presence there.

"We had some real skill and some ability to shoot it but nobody standing in front of the net, which was a real issue for us. We needed to capitalize there and I think when you get one of those in overtime you like to think that you've got a real advantage and unfortunately we couldn't get the thing to go in."

3rd-period rally

The Canadians forced overtime with third-period goals by Joe Hicketts and Daniel Audette and Dineen said the effort his team had to expend to erase its early deficit came back to haunt it later on.

"Yeah, it did," said Dineen, who led Canada's national women's team to Olympic gold in Sochi, Russia. "These players are used to logging a lot of ice time with their respective junior teams but I don't think they're used to logging such hard minutes like they had to tonight.

"That certainly played into it, fatigue at the end."

Jiri Smejkal, Jakub Vrana and Michael Spacek scored in regulation for the Czech Republic, which outshot the Canadians 33-30.

Mathew Barzal also scored for Canada.

The Czechs wasted no time opening the scoring, with Spacek's goal coming just 1:15 into the contest. Vrana made it 2-0 at 7:37 of the second before Smejkal converted on a two-on-one break at 12:57.

Barzal cut Canada's deficit to 3-1 with a power-play goal at 4:51. The Canadians came close moments after, with Ryan Gropp having a great scoring chance off a two-on-one, but couldn't beat Czech goalie Vtek Vanecek. Queeneville also had a glorious opportunity to make it a one-goal game with just over two minutes remaining.

Hicketts pulled Canada to within 3-2 when his wrist shot from the point beat a screened Vanecek at 5:02 of the third before Audette scored off a goal-mouth scramble in front of Vanecek at 12:21.