Pavol Demitra scored to end a marathon shootout and give Slovakia a shock 2-1 win over top- ranked Russia, registering the first major upset of the Olympic men's ice hockey tournament on Thursday.

The stunner capped a day of high drama at Hockey Canada Place, after Canada narrowly avoided a shock of their own when Sidney Crosby scored the only goal in a shootout to lift the hosts to a nailbiting 3-2 victory over Switzerland.

The loss does not end Russian medal hopes in Vancouver but the road to the knockout round became tougher for the world champions, who must now beat the Czech Republic in their final preliminary round game on Sunday to boost their chances of advancing directly to the last eight.

A packed house was treated an Olympic thriller highlighted by a goaltending duel between Slovakia's Jaroslav Halak and Russia's Ilya Bryzgalov.

After three periods and an overtime of lightning-paced end-to-end action the contest was finally decided on the seventh round of the shootout when Demitra banged the puck past Bryzgalov, triggering a stampede off the Slovakian bench who had stood as one with arms wrapped round each other's shoulders.

Canada narrowly avoided a similar fate as their Russian rivals when Crosby fired a laser past Jonas Hiller, who had been spectacular in the Swiss net, to give the hosts the advantage.

WILD CELEBRATIONS

The spotlight then shifted to Canadian netminder Martin Brodeur, the National Hockey League's all-time leader in wins and shutouts, who denied Swiss shooter Martin Pluss to seal a hard-fought win and send the crowd into wild celebrations.

A contest that was supposed to be a small step toward the gold medal final for Canada became a major hurdle as the Swiss rekindled memories of the Turin Games. It was there the Alpine nation pulled off the biggest upset in ice hockey history by beating Canada, the reigning Olympic champions, 2-0.

The Swiss appeared poised to inflict an even bigger surprise as they clawed back from two goals down in front of a raucous Canadian crowd to force a shootout.

As a coach you want to win every game but every championship I've been involved with you're team has to go through adversity and that's what we had here today, Team Canada coach Mike Babcock told reporters. In order to win at this level of competition you need to get better every game.

I think this is a huge step for our team to understand how hard it is going to be and how well we are going to have to play.

The victory set up a Group A showdown Sunday with the United States, who earlier also improved to 2-0 with a 6-1 win over Norway.

The United States lead Group A with six points, followed by Canada with five. Switzerland earned their first point of the tournament in the shootout loss while Norway have no points.

Despite the loss Russia cling to top spot in Group B with four points followed by the Czechs on three, Slovakia two and Latvia zero.

The top four ranked teams at the end of preliminary round play automatically qualify for the quarter-finals.