INDIANAPOLIS, AUG. 10 -- The cream of Argentina's starting basketball team was a no-show today, but Greg Louganis was all show at the Pan American Games tonight.

Any lack of drama caused by the Argentines' absence -- sentencing their B squad to a 27-point defeat by the United States -- was made up for, especially from the host nation's vantage point, with a day of swimming victories, an evening of track and field successes and Louganis' performance in capturing the gold medal in springboard diving, becoming the first man to win three Pan Am medals in one event, and falling just one point shy of his world record in the process.

Louganis scored perfect 10s seven different times for a total score of 754.14, his second best ever, to break his mark of 724.02 set in 1983. He led the field of 11 other divers from the very first compulsory, and his score was just shy of his world-record 755.49 set in Fort Lauderdale, Fla., in 1983.

"One point, wow," he said. "I figured I was nearing the record but I didn't know how close. I knew I was diving well and I was just concentrating on doing a good dive."

Doug Shaffer of the United States won the silver with a score of 684.39, but never seriously threatened Louganis.

Louganis has won the springboard gold twice previously, in 1979 and 1983. Should he capture the platform this year, he would be the first diver to accomplish a triple-double. With tonight's medal, Louganis also surpassed Juan Capilla of Mexico for most gold medals ever won in diving; they had been tied at four. Capilla won his four in 1951 and 1955.

Louganis called it his best performance of the year. Had he made just one higher score in any of the seven judging places over his last three dives, he would have broken his world mark.

"I felt good, strong, and like things were rolling," he said. "Overall, I was really pleased. I was consistent, and that's going to win meets."

After the medal ceremony, Louganis returned to the nearly empty stands, where he slipped his medal around the neck of 14-year-old Bryan White, an AIDS victim from Fort Wayne, Ind., and chatted with him for several minutes.

In swimming, Silvia Poll of Costa Rica captured a gold medal in the 200-meter freestyle over Americans Whitney Hedgepeth and Sara Linke, and Anthony Nesty of Surinam broke his own Pan Am 100-meter butterfly record with a time of 53.59 to come from behind and defeat Wade King and Duffy Dillon of the U.S.

Nesty, a 19-year-old resident of Jacksonville, Fla., had set the Pan Am record in the preliminary heat with a time of 54.06. He came from behind on the final length to edge out King (54.33) and Dillon (54.45) and give Surinam its first Pan Am medal of any kind.

"It scared me at first," said Nesty of his competition. "My coach told me they go out pretty fast, but coming back I got more confidence in myself."

The former record was 54.25 by American Matt Gibble at Caracas in 1983.

Poll, 16, had given Costa Rica its first gold medal with her victory in the 100-meter freestyle Sunday. Today, she made it two with a time of 2:00.02, winning by a breath over Hedgepath at 2:02.06 and Linke at 2:04.00.

John Witchel, who won the 200 freestyle Sunday, anchored the United States' winning 800-freestyle relay team that set a Pan Am record.

U.S. swimmers finished one-two in the men's 400-individual medley, with Jerry Frentsos taking the gold medal with a time of 4:23.92, Jeff Prior of Philadelphia was second at 4:26.31 and Canada's Mike Meldrum was third at 4:29.63.

Dorsey Tierney of Louisville gave the United States another gold in the women's 200 breaststroke (2:36.87).

There was little suspense in the U.S.-Argentina basketball game, with seven of Argentina's top players left at home and the "B" team obviously outclassed as the United States won, 85-58, at Market Square Arena. Argentina, which had beaten a U.S. team at the world championships last summer, was supposed to be one of the few things standing between the U.S. and gold here.

Instead, four U.S. players were in double figures -- Rex Chapman, Dean Garrett and Willie Anderson with 11 points each and David Robinson with 10 -- as the Americans led by 31 points in the last two minutes. Without four starters and the sixth and seventh men off the bench, Argentina was outrebounded, 47-28.

"We were sorry Argentina's full team couldn't be here," Coach Denny Crum said. "I know they were disappointed, and we were looking forward to playing their best team. But give them credit. They got the most out of their talent."

Argentine Coach Flor Melendez would not discuss the reason for his first team's absence, but it was believed the six players boycotted the games in a financial dispute with their federation.

They pulled out two days before they were scheduled to come here, reportedly despite Melendez's offer of money out of his own pocket. Some members of the team that Argentina finally brought here made their plane with 20 minutes to spare, the coach said.

The team that came instead was a young one with heart but little substance, beyond a nifty guard (Marcelo Milanese with 17 points including three three-pointers) and forward (E. Perez Espeanzza with 16 points).

Argentina stayed close in the first half, cutting an 11-point deficit to 35-32 with 3:22 to go, when Milanesio scored five straight points. But the U.S. scored seven straight points, including a three-pointer by Chapman and a slam by Robinson, to lead by 42-34 at the half.

It was no contest in the second half as the U.S. wore out Argentina's thin resources. The Americans went on a 20-8 run to take a 62-42 lead, including six points from Manning.

Perhaps the prettiest play of the afternoon came on a three-point play from Robinson on a jam and free throw that made it 81-50 with 1:54 left.

Two injured U.S. players, Jeff Lebo and Fennis Dembo, showed no ill efects today. Lebo had taken a shot in the nose and Dembo one in the eye in the victory over Panama Sunday. Against Argentina, forward Ricky Berry slightly resprained an ankle and saw just limited time, although he is expected to bounce back quickly.