The U.S. men’s hockey team beats Canada in a preliminary game.

The United States’ stitched-together men’s hockey team turns out to have some pluck: It steered past Canada, which has won medals at the last three Olympic Games, in a preliminary game on Saturday, 4-2.

Both the Americans and Canadians had expected to fill their rosters with N.H.L. stars, but the league’s decision in December to withdraw from the Beijing Games left both countries scrambling for players elsewhere. The result for the Americans was their youngest team since 1994, but they hardly seemed daunted by the big stakes in Beijing, even after Canada scored just 94 seconds into Saturday’s matchup.

Just more than a minute later, Andy Miele lobbed the puck — the first American shot of the day — past Eddie Pasquale, Canada’s netminder, for a goal that evened the score. The United States claimed the lead late in the first period, when a thicket of American and Canadian players near the goal sprouted enough chaos for Ben Meyers to score.

The United States added to its advantage early in the second, as Pasquale returned from behind the net to find a fast-swarming Brendan Brisson hammering the puck his way. The goal horn sounded again.

The Canadians, though, tightened the game with a goal from Corban Knight as their captain, Eric Staal, waited out an elbowing call. Staal, 37 and back in the Games for the first time since 2010, celebrated alone in the penalty box.

A powerful shot from Kenny Agostino, who had just seen Miele tap the puck toward him after a Canadian turnover, pushed the American lead to two goals — and Pasquale’s misery higher — with about 14 minutes to play in the third period.

Later in the period, the Canadians proved unable to score when, for a brief spell, two Americans were serving penalties. Canada pulled Pasquale from the net with about two-and-a-half minutes to go.

Claude Julien, a Stanley Cup-winning coach, was in charge of the Canadian team for the first time during the Games on Saturday, having sufficiently recovered from fracturing ribs when he slipped on ice during a team activity in Switzerland last month.

His team will face China on Sunday night, when the United States, which has not won an Olympic medal in men’s hockey since it took silver in 2010, will meet Germany at a different arena in Beijing. The men’s tournament’s elimination games are scheduled to begin on Tuesday.