SEOUL, SEPT. 20 (TUESDAY) -- In the most dramatic event of the Seoul Olympics so far, Greg Louganis won the springboard diving Tuesday despite hitting his head on the board in preliminaries Monday night.

On a day the U.S. men's basketball team had to rally to defeat Canada and a disqualified U.S. boxer's appeal was denied by his international federation, Louganis' comeback from near disaster was the talk of Seoul, and perhaps much of the world as well.

Trying to become the first man to successfully defend Olympic championships in both springboard and platform diving, Louganis hit the back of his head as he was attempting a reverse 2 1/2 somersault in the pike position on the ninth of his 11 dives in the qualifying round of the springboard competition Monday.

He got out of the water without help, rubbed the top of his head and smiled, then went off to get medical attention. Judges gave him a total of 6.3 points that included two zeroes, one .5, three 1s and one 1.5, pushing him to fifth place.

He came back about a half-hour later with five stitches in his head, and had his best dive of the day.

When he appeared on the deck at Chamshil Indoor Pool Tuesday morning for the finals, many in the crowd stood and cheered. But Louganis' opponents, specifically China's Tan Liangde and Le Deliang, were not about to hand anyone a gold medal.

The 28-year-old Californian, with his wound visible on his head, all but clinched the gold on the same dive that could have caused him serious injury Monday. This time, performing the reverse 2 1/2 from the pike position, Louganis cleared the board easily and earned a score of 76.50.

Louganis completed his performance with two of the most difficult dives, a reverse 1 1/2 with 3 1/2 twists, for which he earned a score of 88.11, the highest score of the competition, and a reverse 3 1/2 from the tuck position, which carries the highest degree of difficulty, 3.5.

Louganis, finished with 730.80 points. Tan, 23, who has beaten Louganis twice this year and is the only man to defeat him on the springboard in international competition since 1981, totaled 704.88. Li, 21, had 665.28.

In other developments, the U.S. men's basketball team survived an early scare from the Canadians but rallied for a 76-70 victory as Georgetown's Charles Smith hit two critical three-point shots down the stretch and scored 10 points.

But there was no second chance for another U.S. athlete, as boxer Anthony Hembrick's medal hopes ended when he lost an appeal submitted after he showed up late for a bout and was disqualified. The International Olympic Committee was asked to get involved in the case by the U.S. delegation, but no decision was expected until later Tuesday.

In the medal race, the Soviet Union had seven, including three golds; China had six, including one gold; and the United States had five, including two golds.

Hembrick, the Detroit middleweight, was disqualified Monday for arriving late for his first-round match against South Korean Ha Jong Ho. Ha's hand was risen in victory just as Hembrick and U.S. Coach Ken Adams came rushing into the boxing arena.

Adams and Hembrick, believing they were the 11th bout of the morning, missed the 10 a.m. bus to the boxing venue, but they thought Hembrick's fight couldn't start before 12:45 p.m. The 10:30 bus got Hembrick to the venue at 10:52, when he found out he and his coaches had misread the schedule.

The U.S. team appealed the disqualification, but by a vote of 3-2 the grievance committee of the Amateur International Boxing Association turned down the appeal, ending Hembrick's Olympics before they had started.

Mindful of his teammate's problems the previous day, welterweight Kenneth Gould arrived at the Chamshil Students Gymnasium nearly three hours early for his bout Tuesday. He then decisioned Joseph Marwa of Tanzania, 4-1, Tuesday to give the United States its first good news in Olympic boxing in three days.

Gould took a first-round standing eight-count and had more trouble than expected in winning.

The U.S. women's volleyball team, however, lost its first game of the Olympics Tuesday night, routed by the top-ranked Chinese, 15-9, 15-5, 15-7.