BARCELONA ’92 OLYMPICS / DAY 7 : Montell Griffin Wins but Angers Coach : Boxing: The U.S. light-heavyweight showboats in waning seconds of 16-1 decision over South Korean. With three other victories, Americans are 12-2.

Montell Griffin spent three rounds beating up a South Korean in the Olympic boxing tournament Friday, and U.S. Coach Joe Byrd liked everything about it except the last five seconds.

Griffin, his 16-1 light-heavyweight decision in hand, decided to take a victory lap in the final seconds. He skipped counterclockwise around the ring, right hand held high, to the accompaniment of jeers and whistles by many in the crowd of 1,500.

Watching all this from the center of the ring was the beaten--and exhausted--Korean, Ko Yo Da. Byrd grabbed Griffin and gave him an earful just before the decision was announced.

It was an unseemly incident on a day the U.S. team raised its tournament record to 12-2--Cuba is 14-1--with four victories. Middleweight Chris Byrd, the coach’s son, won a decision; super-heavyweight Larry Donald stopped his opponent with two seconds to go; and heavyweight Danell Nicholson won a decision, setting up a match against world amateur champion Felix Savon of Cuba.

Oscar De La Hoya of East Los Angeles, Pepe Reilly of Glendale and two other Americans will box today in second-round matches.

Eric Griffin, the gold-medal favorite at light-flyweight, will meet Spain’s Rafael Lozano; bantamweight Sergio Reyes will box North Korean Li Gwang Sik, and Reilly will face Lithuanian welterweight Vitalijus Karpaciauskas in the afternoon session. At night, De La Hoya will fight Nigerian lightweight Moses Odion.

The powerful Cuban team also scored four victories Friday.

Despite the fine day’s work by the U.S. boxers, Joe Byrd was hot. He said Montell Griffin had shown up his South Korean opponent and possibly upset some judges.

“I was never a showboat myself when I boxed, I just don’t like that stuff,” Byrd said.

“I told him that, and I’m going to tell him some more. We’ll take him back and give him the third degree about it and he’ll be all right.”

Griffin, ruefully, had much the same version of Byrd’s lecture.

“He told me I shouldn’t show off,” he said.

“He said: ‘You got a couple of fights left here--why get the judges against you?’ ”

The muscular, 5-foot-7 Griffin, sporting his Joe Frazier-style baggy, knee-length shorts, again won with his jitterbugging, punch-slipping style--spiced with an assortment of stinging jabs and jolting shots to the ribs.

But things soon will get much tougher for him. In Tuesday’s quarterfinals, he will fight world champion Torsten May of Germany.

When asked about May, Griffin shrugged.

“John Ruiz beat May in the States (at a USA-Germany dual meet in West Palm Beach, Fla., in April) and I beat Ruiz, so what does that mean?” he said. “I’m going to stay in his chest, jab him and make him miss.”

Nicholson, from Chicago, scored a 9-6 decision over a tough Croatian, Zeljko Mavrovic, rocking him with a straight right hand with 48 seconds left.

Savon, who will be Nicholson’s quarterfinal opponent Monday, was impressive again Friday in trimming German Bert Teuchert, 11-2.

Still, Nicholson seemed quietly confident that he can upset Savon, considered by many the second-best bet for a gold medal here, behind Eric Griffin.

“I’m not going to run from him, I’m not hidin’,” Nicholson said. “Every fighter has to think he can win.

“I’m in shape, he’s in shape. May the best man win.”

Savon has held the world championship off and on since 1986. He is 24, as is Nicholson, but has had hundreds of amateur bouts, compared to about 30 for Nicholson, who took up boxing two years ago.

Chris Byrd became the first American to reach the quarterfinals with a 16-7 victory over Alexander Lebziak of the Commonwealth of Independent States. Byrd stands an excellent chance of reaching the medal round, in that he figures to be the favorite over his Sunday opponent, Ahmed Dine of Algeria.

Byrd, much to the annoyance of his father, spent much of the bout on the ropes against Lebziak, slipping his punches and countering. He had a lead of 10-4 after two rounds and won the third handily.

“I like fighting off the ropes, but it makes my father nervous,” he said, laughing.

“The judges were giving me (scoring) those counterpunches on the ropes, so I might stay on the ropes the rest of the tournament.”

Asked if he could hear his mother, Rose, cheering from her balcony seat, Byrd said: “I sure could. She was screaming louder than anyone. She’s tougher on me than my father is.”

Against Nikolai Koulpine of the CIS, Donald employed a busy jab, used the entire ring and had a shutout in hand, 8-0, when the bout was stopped two seconds into the third round.

The referee refused to allow Koulpine to continue because of a cut on his right eyelid.

Donald was outraged that the judges had credited him with only a 1-0 lead after the first round.

“Coach Byrd said to me after the first that the score was one to nothing,” Donald said.

“I said: ‘Really? Who’s winning?’

“One to nothing? That’s ridiculous. It should have been more like 20-0.”

Donald will meet Cuban champion Roberto Balado in Tuesday’s quarterfinals and says it will be the equivalent of a gold-medal bout. Balado overwhelmed Canada’s Tom Glesby in a 16-2 decision in the bout preceding Donald’s.

“This will be for the gold medal,” Donald said. “We’re the two best boxers in the tournament.”

Friday’s most impressive performer was Cuban Ariel Hernandez, a new face. His 13-2 victory over Gilberto Brown of the Virgin Islands was a dazzler. He showed every punch in the book, great hand and foot speed and solid defensive skills. He looms as a possible gold medal opponent for Chris Byrd.