Whenever American athletes and officials were asked during the first few days of competition here about how few medals the United States had won, the U.S. athletes would say, "Just wait until track and field, and diving events."

And sure enough, the Americans had success in those events today, winning a gold medal in diving and a gold and a silver in athletics (track and field). Greg Louganis easily won the three-meter springboard competition.. And tonight, in rainy Commonwealth Stadium, Michael Carter earned a gold in the men's shot put and Randy Givens of Florida State won a silver medal in the women's 100-meter dash.

Great Britain hadn't been a factor until today, when Beverley Kinch ran the women's 100 meter in 11.13, which enabled her to edge Givens and win a gold medal. In the men's hammer competition, Yuri Tamm won the gold for the Soviet Union, but Great Britain's Richard Weir finished second to take the silver.

In the diving, what little suspense left after eight tries in the three-meter event was shattered on the ninth. Leading his nearest competitor by 26 points, Louganis decided to make his ninth dive something special: a 1 1/2 somersault with a 3 1/2 twist. Louganis was awarded 86.13 points for the dive, including two scores of 9.5, to achieve the best performance of the day, by far.

Louganis' 671.43 points won easily over silver medalist Niko Drozhzhin of the Soviet Union (605.97) and bronze medalist Liangde Tan of China. Ron Merriott of Eastern Michigan finished fifth.

Americans won two silver medals in tonight's swimming competition, but finished behind the Russians in three events. Marybeth Linzmeier from Stanford placed second in the women's 800 meter freestyle behind Irina Laricheva, who won her fifth gold medal. Pam Ratcliffe of Southern Illinois finished second in the 200 meter individual medley, one second behind the Soviet's L. Belokon.

In basketball, the U.S. men's team completed the qualifying round with a 99-84 victory over Cuba tonight at the Universiade Pavilion.

Now, the United States advances into the medal round, and will play Canada or Yugoslavia Friday.

The United States, after shooting over 70 percent in some of its earlier games, found Cuba's defense much tougher than expected and shot only 47 percent tonight. Johnny Dawkins of Duke scored 19 points, but made only seven of 16 shots. Ed Pinckney of Villanova also scored 19, but made just seven of 14 from the field. Bernard Thompson, from Fresno State made only five of 13 shots, but had 15 rebounds.

Eric Turner of Michigan made nine of 12 shots and finished with a game-high 22 points. The United States limited Cuba to 36 percent shooting.