The U.S. Naval Academy learned today why professional boxing often is referred to as "the red-light district on sports."

The switchboard lit up with telephone calls afer heavyweight Johnny Boudreaux was awarded a unanimous eight-round decision over Scott LeDoux in the heavyweight finisher of the second set of quarterfinals in Don King's U.S. tournament.

One caller said, "I didn't think much of the fight, but the decision was worse."

The whole affair ended in a brawl at ringside when LeDoux heard Boudreaux refer to him in a television interview on ABC as a chump. He tore across the ring, punched at Boudreaux and then kicked him in the face.

Worse, when some calm was restored, LeDoux was interviewed on television and said that he was told before coming here that he could not win without a knockout because Boudreau was owned by promoter King, matchmaker Al Bracerman and Paddy Flood, who worked in Boudreaux's corner.

Shortly before that, Joe Daszkiewicz, LeDoux's manager, stood in the ring and shouted down at King at ringside, "We didn't know till we got here that most of the fighters are owned by you, Braverman and Flood."

King did not reply to Daszkiewicz.

Braverman was asked later if he had any financiagninterest in Boudreaux.

"Did you ever hear a manager admit his fighter has lost a bout?" Braverman countered, rhetorically. "I don't own any part of Boudreaux and neither does Don King. He is owned by two . . .guys whose names I don't know. They pay him 300 a week. Flood was just working in his corner on an individual-bout basis.

"One referee was from Philly, one from New York and one from Washington; they're neutral."

Referee Joe Bunsa of Washington voted three rounds for Boudreaux, two for LeDoux and three even. Harold Valan of New York voted it 5-3, Boudreaux, and woman judge Carol Polis of Philadephia had it 4-3 with one round even.

Jack Cohen, executive secretary of the Maryland State Athletic Commission, said the fights were by rounds instead of the usual five-poin-must system in Maryland because Don King Productions asked the waiver so as to make the scoring uniform for the tournament bouts in various parts of the country.

Cohen said, "They also asked us to use some outside referees, although we offered them six of our officials. Only one of our officials worked the bout in controversy, Bunsa."

It ended amid boos from a crowd of 7,500 in Halsey Field House.

LeDoux knocked down Boudreaux in the second round and appeared to have the edge in the eight-round bout that was hooted after nearly every other round because there was so little action.

Whether he meant it or was merely trying to motivate LeDoux, manager Daszkiewicz said before he start of the final round, "We need this round."

When the fight ended, LeDoux leaned over the ropes and shouted to promoter King, "I told you - give me an easy fight and I'd win . . . It was an easy win."

The words were barely out of his mouth when it was announced that Boudreaux was awarded the decision.

LeDoux was disconsolate but relatively calm until he danced near the ABC microphone and heard the chump reference.

As LeDoux charged down at Boudreaux, the latter arose and there was a knocking-about of persons such as George Foreman, who was the ABC analyst, and sportscaster Howard Cosell.

A kick by LeDoux dislodged Cosell's toupee and the announcer was seen hurriedly adjusting it.

Until all that fuss, Leo Saenz of Potomac and Casey Gasic of Cleveland had stolen the show with a furious middleweight bout that also stirred some controversy.

Saenz dropped Gasic three times but Gasic was awarded a unanimous decision. Polis voted three rounds for Gasic, two for Saenz and three even. Referee Larry Barrett had it 4-2-2 and judge Valan 5-3.

In contrast to matchmaker Braverman's skepticism about fight managers being objective. Barry Locke, Saenz's manager, said, "I thought Gasic won. Leo can beat anybody in the world when he is in shape but he did nottrain the last three weeks."

Another area fighter figured in a controversial finish, light heavyweight Biff Cline, a former Washington policeman managed by his father, Chris.

Cline, 176, who had a 13-0 record, all by knockouts, was stopped after 1 minute 48 seconds of the fourth round by Ray Elson, 177 1/2, in a furious sluggling contest.

The advantage seesawed for three rounds but Cline's nose was squashed in the second and his breathing was bothered the rest of the way. Cline was virtually helpless when his father threw in a bloody towel, but it caught on a lower strand of the ropes without referee Valan seeing it.

Almost simultaneously, the elder Cline tore through the ropes to save his son from further punishment and Valan put an end to the proceedings. Afterward, Valan said he was about to stop the bout.

Washington welterweight Johnny Gant, 146 1/2, ended his bout with Anthony House, 148 3/4, spectacularly at 1:43 of the second round.

During an initially light exchange, Gant suddenly rocked House with a right hand to the head and followed up with a flurry of punches as his opponent stumbled backward about the ring. Gant then dropped House with a right cross to the jaw in a neutral corner and when the count reached nine Valen stopped the bout.

Featherweight Richard Rozelle, 123 3/4, won a unanimous decision over David Vasquez, and Edwin Viruet, 134 1/2, stopped Tommy Rose, 134, after 2:49 of the fourth round, referee Bunsa stepping in to end it.