THE WORLD CUP : Costa Rica’s Hearts (and Feet) Upset Scots : Group C: Goal in 49th minute, game-saving stop by goalkeeper give Central American team a stunning 1-0 victory.

What the United States couldn’t manage, Costa Rica did.

The Costa Ricans, who finished ahead of the Americans in qualifying for the World Cup, were as lightly regarded as the U.S. team.

But in their debut among the elite of soccer, they got a goal from Juan Cayasso on a superb feed from Claudio Jara and outstanding goalkeeping by Luis Conejo for a 1-0 victory over Scotland Monday.

In its opener Sunday, the United States was beaten badly by Czechoslovakia, 5-1.

“I’m very happy for Costa Rica, which is a small country but has a big heart,” said Coach Bora Milutinovic, a Yugoslav who took over the team in February. He also coached Mexico to the quarterfinals in 1986.

“I’m moved by all the players’ effort. They played very well and showed great tactical discipline.”

The Costa Ricans, who qualified ahead of the United States in the North and Central American and Caribbean group, were outplayed for much of the game and particularly after Cayasso scored in the 49th minute.

But Scotland could not beat Conejo, whose diving arm save on Maurice Johnston’s point-blank shot in the 65th minute was his best stop.

“Luck is often important,” Conejo said. “Mo Johnston is a great player. But we worked very hard with Bora to get this result.”

All the Costa Rican players wore black armbands in memory of the founder of Costa Rica’s 1948 constitution, Jose Figueras, who died last week.

Costa Rica’s victory was the third upset of the tournament. Cameroon stunned defending champion Argentina in the opener, and then Romania surprised the Soviet Union.

Cameroon and Romania have been here before. But the Costa Ricans never had dealt with World Cup pressure.

Cayasso beat goalie Jim Leighton from close range with his left foot. But the goal was set up by Jara, whose clever back pass with his heel while closely covered sprung Cayasso to the right of Leighton.

From there on, Scotland attacked furiously. But Conejo and the Scots’ poor marksmanship did in them in.