On a day of enthralling action in Bratislava and Kosice, the Czech Republic were the only side to enjoy a smooth ride into the last four with a 5-1 drubbing of underdogs Germany.
The Russians edged old rivals the United States 4-3 and Canada also needed overtime to beat last year's runners-up Switzerland 3-2 after grabbing an equaliser four-tenths of a second before the end of regular time.
Saturday's semis will pit Russia against Finland while Canada face the Czech Republic. The final is on Sunday in Bratislava's Ondrej Nepela Arena.
The Russians, who had romped through the group stage with seven straight wins, dominated the opening period and Nikita Gusev and Mikhail Sergachyov gave them a 2-0 lead.
The Americans pulled one back through Brady Skjei but Gusev fed Kirill Kaprizov for Russia's third and Mikhail Grigorenko rounded off another lightning break to make it 4-2 after Noah Hafinin had reduced the arrears with a backhander.
The Russians were forced to hang on after Alex Debrincat rifled in a first-time shot from Patrick Kane's assist and the U.S. piled on late pressure.
"It’s disappointing because we had high expectations, so we’re not happy our tournament’s done so quickly," Skjei said.
"They’re a really good team. We know that, but we’ve got a good team too and we thought we could beat them, and I still think that we could have."
SWISS DISCONSOLATE
The Swiss, who beat Canada 3-2 in last year's semi-finals, were disconsolate after losing by the same score this time as the Canadians snatched victory from the jaws of defeat.
Power-play goals by Sven Andrighetto and Nico Hischier wiped out Mark Stone's equaliser for Canada, who looked down and out before Damon Severson's shot ricocheted off several bodies and trickled over the line to force overtime.
Stone emerged as Canada's hero when he steered in a Pierre-Luc Dubois pass to spark wild celebrations among his team mates.
"I saw the puck go in and that’s all I could tell you, really," Severson said. "I didn’t know how much time was left. It ended up being the tying goal so that was awesome."
The Swedes stormed back to take a 3-1 lead after falling behind early and after conceding twice in quick succession, they were 4-3 up after a bizarre goal late in the second period.
Having initially allowed played to continue as the puck appeared to have struck the upright, the officials awarded Erik Gustafsson's goal only after video replays showed it went in and smashed the mini-camera strapped to the back of the net.
However, the Finns had the last laugh as Marko Antilla forced overtime with a goal late in the third period and Sakari Manninen produced the final twist with a fine solo effort.
Germany were level 1-1 with the Czechs after the opening two periods but ran out of steam in the final 20 minutes, with Jan Kovar scoring twice for the winners.
(Reporting by Zoran Milosavljevic; Editing by Ed Osmond)
