In their room a few floors above the heavily guarded lobby, the sophisticated Washington-area international travelers were comparing impressions.

Paris and the scenes nearby were as he had imagined, said Duke's Tommy Amaker of Reston, Va. And the Soviet Union, several years ago, had been a more pleasant experience than he had anticipated.

Except for the time he found himself all alone in defense of the U.S. basket, with the imposing Arvidas Sabonis leading a three-man Soviet breakaway.

Amaker is slender and 5 feet 10, Sabonis well proportioned and 7-3. Barely out of W.T. Woodson High School at the time, Amaker wisely opted to keep all his bones in their proper place, stepping aside and sort of saying: "Mr. Sabonis, the lane is free; dunk to your delight."

Which, in backboard-rattling fashion, he did.

On a bed elongated to accommodate his near-7 feet, Navy center David Robinson of Woodbridge, Va., was mentioning his surprise at how cocky the rest of the countries have seemed. Especially the French. Do the French ever talk trash!

Because they play basketball exceptionally, Amaker and Robinson have seen the world as few others have. Because they are part of the U.S. team in the semifinals of the World Basketball Championships, the hotel resembles a fortress.

For the first-round games in Malaga, police on motorcycles stayed slightly ahead of and slightly behind the team bus. A helicopter hovered overhead. Neither Amaker nor Robinson uttered a peep of protest over being close to hermetically sealed.

On the court, the U.S. team has moved in all-too-typical fashion: slowly and without cohesion early but gathering momentum for an expected collision with the Soviets in the final round.

If Americans still play the game much better, most other countries take it more seriously at the international level. With no pro league for competition, the Soviets have played together on tours for years.

The U.S. players only got their traveling orders, after a series of tryouts, several weeks ago. Robinson had just crawled away from submarine duty before making the team.

His eyes twinkled.

"There's more room on a sub than people think," he said.

So Robinson's frame had not needed reassembling after the three-week cruise. Still, his play has been superior of late.

He had 19 points and eight rebounds during a narrow victory over Puerto Rico two games ago. In the most recent test, against the seemingly strong Italians, he had 14 points, 10 rebounds and six blocked shots.

What was seen as a very competitive game before the opening tip became a 22-point U.S. victory that caused the team to arrive here for the semifinals full of confidence.

Robinson is adapting to the more rugged international game, where whistles are infrequent and inconsistent. During a tournament in Spain last year, his style was considered soft.

As this tournament has progressed, Navy's best-ever player has become tougher. Skeptics have been impressed the last two games.

"There's been no fighting," Robinson said. "But there have been times when I've been jolted, seen stars for a second."

Amaker said: "Everybody in Europe has been saying: 'The Americans are too young most are rising seniors in college and not physical enough.' "

Once indifferent about basketball, Robinson has fallen in love with it in slightly more than a year.

"It's the biggest part of my life now," he said, "because it's done the nicest things for me. I have to put the time back into it. I've gotten to play with the best players and against really good competition.

"How else would I also have gotten to see the places I've seen."

Somehow, he would like to maneuver playing in the Olympics and the NBA with his obligations to the Navy. He hasn't the foggiest notion how all three might be juggled.

Navy and the 1988 Olympics easily could be arranged. But would Robinson be able to get the necessary competition, during his year after graduation from the Academy, to stay sharp for the Olympic trials?

He shrugs.

"It's a matter of how long and how hard I work wherever I might be," he said of that season between graduation and the Olympics. "It's all up to me eventually anyway."

Also, he said, "Somewhere down the line I'd like the opportunity to play in the NBA. That's one of my goals."

He shrugs again at how that might come about.

Of more immediate concern is the next U.S. opponent here: Argentina on Sunday. On Monday comes Canada and then a team also unbeaten in the first round, Yugoslavia.

"The thing I've noticed about players from other countries," Robinson said, "is how they don't really look like they'd be much good at basketball. But they are.

"They seem like they ought to be playing soccer. Or football. The Italians have a guy maybe 6-4 and 230, linebacker size. He doesn't look like he'd be able to penetrate or pass. He really could."

Robinson also was surprised at how often non-American journalists have approached him and his teammates and asked "if we think we will win."

"Americans," he said, "assume we have a chance to win or we wouldn't be walking on the court."

From a distance, he sees the Soviet team as having "great size and great confidence. That's the main thing. If you go out on the court like you think you're the best, you'll play well."

Amaker nodded agreement.

He and another defensive specialist, 5-foot-3 Tyrone Bogues of Baltimore and Wake Forest, would be factors as important as Robinson in a U.S.-Soviet matchup.

For the U.S. to win, Robinson would have to frustrate Sabonis. That would be so much easier if his little buddies, especially Bogues, could keep the Soviet point guard from getting the ball to his center.

"Muggsy's fast, and sees the court well," Robinson said of Bogues. "He's a lot better than I thought." In about a week, Robinson would like the trash talkers to say the same of him.