The United States kept its hope alive for a fifth straight gold medal at the IIHF World Under-18 Championship in Sochi, Russia, with a 4-0 defeat of Sweden in the quarterfinals Thursday.

Thatcher Demko, a top prospect for the 2014 NHL Draft, stopped all 28 shots he faced, and four prospects for the 2013 draft -- Will Butcher, Tyler Motte, Michael McCarron and JT Compher -- supplied the offense in a game played at Shayba Arena.

The United States had beaten Sweden in the gold-medal game the past three years, and playing two rounds earlier in the 2013 tournament, the result was the same.

"We knew that we'd have to be at our very best facing a talented Sweden team," U.S. coach Don Granato said. "Our goal is to get stronger and stronger each game. We're happy with the performance [Thursday], but will continue to work hard [Friday]."

The United States took the lead on a power-play goal at 13:14 of the first period by Butcher, No. 87 in NHL Central Scouting's final ranking of North American skaters for this year's draft. He got the rebound of his own shot off the end boards and beat Sweden goalie Jonas Johansson. Motte, No. 84 in Central Scouting's final rankings, scored on a pass from Hudson Fasching with 2:29 left in the period to make it 2-0.

After a scoreless second period, a power-play goal at 6:50 of the third by McCarron, a defenseman ranked No. 35 by Central Scouting, made it 3-0. Compher, No. 34 on the final list, scored an empty-net goal with 4:52 to play to close the scoring.

Demko made the lead hold up, stopping every shot thrown his way, including 20 in the second period. That period saw Sweden get four of its seven power plays, including a stretch of 1:50 where the United States was down two men.

"There's no question that when a team sees its goaltender play great, then it's a huge boost," Granato said. "He [Demko] is capable of what he did today. We hadn't seen that yet at the tournament, I think he overthought things earlier in this tournament and that had him struggling a bit, but today should be a huge boost for his confidence and his performance."

The United States will play Russia in one semifinal Friday. The host team got a hat trick from top 2013 draft prospect Valeri Nichushkin en route to an 8-4 win against Germany in a game played at Bolshoy Ice Dome.

Nichushkin, No. 2 on Central Scouting's final ranking of European skaters for this year's draft, opened the scoring with a power-play goal 1:42 into the game. He added a goal 1:47 into the second to give Russia a 3-1 lead, then closed the scoring with a goal with 6:21 left in the third.

"This is one of the best games he has played," Russia coach Igor Kravchuk said. "His emotional status lifted. He was charged up for scoring."

In the other semifinal Friday, Canada will face Finland.

Connor McDavid, the 16-year-old budding star, had a hat trick for the second straight game when  Canada beat the Czech Republic 6-0 in a quarterfinal at Shayba Arena.

With Canada leading 1-0 after one period, McDavid, who already has pushed his name to the top of the rankings for the 2015 draft, scored with 1:29 left in the second period to give Canada a 2-0 lead. Twenty-six seconds later, Nick Baptiste scored to make it 3-0 for Canada.

McDavid capped the hat trick with goals 2:46 apart in the third period to make it 5-0. He tops all players in the tournament with eight goals and 14 points in five games.

"Sure, it is nice to get a couple of points," McDavid said, "but it is all about the gold medal."

Philippe Desrosiers, No. 7 on Central Scouting's final ranking of North American goaltenders, made 19 saves to register the shutout. In three games he's stopped 72 of 73 shots, and leads the tournament in goals-against average (0.33), save percentage (.986) and shutouts (two).

"It's huge, but it's getting kind of repetitive because they both keep on having great games," Canada captain Sam Reinhart said of the play of McDavid and Desrosiers. "The more important thing right now is that everyone is bringing their 'A' game at the right time."

Reinhart and Laurent Dauphin also had goals for Canada.

Finland scored three times in a 1:26 span early in the third period to blow open a tie game against Switzerland and win 7-4 in their quarterfinal game, at Bolshoy Ice Arena.

Mirco Mueller, No. 9 on Central Scouting's final ranking of North American skaters, and Pius Suter scored late in the second to tie it 3-3 after 40 minutes.

But in rapid-fire succession in the third, Aleksi Mustonen, Joose Antonen and Janne Puhakka scored to give Finland a 6-3 lead.

"We were ready for that third period and were powerful from the beginning," said Mustonen, who also had a pair of assists.

Antonen and Juuso Ikonen, No. 23 on Central Scouting's final ranking of European skaters, each had a pair of goals and an assist. Artturi Lehkonen, No. 9 on the list, had three assists.

Yannick Rathgeb scored for Switzerland midway through the period to make it 6-4, but Finland's Jonathan Tanus replied with a goal 1:23 later for the final margin.

The semifinal games will be played at Bolshoy Ice Dome. The bronze-medal and gold-medal games will be played Sunday at the same building.

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