Mark Johnson, boxing's little wonder at 115 pounds, missed an almost perfect opportunity last night to defend successfully his International Boxing Federation junior bantamweight title at the D.C. Armory when his scheduled 12-round bout was ruled a no-contest after Johnson hit challenger Raul Juarez low during the fourth round--and Juarez could not continue.

The fight, which Johnson dominated, was ruled a no-contest because it did not go four rounds. The blow was ruled accidental.

Johnson (38-1) knocked out Juarez (28-5) in the eighth round in August 1996 and was on his way to an even more impressive victory when it appeared that the pride of Washington became frustrated by Juarez's desperate roughhouse tactics. The southpaw Johnson, 28, had punished his foe from Mexico City from the outset as a partisan crowd of about 2,000 chanted his nickname, "Too Sharp."

But Johnson, in quest of his 27th knockout, lost his huge advantage, amassed on compact and brutal punching, when he hit low in the last minute of the fourth. Juarez crumpled, his face coiled in pain. He then toppled onto his back and lay stretched flat. After a ring doctor ruled that Juarez could not continue, referee Joe Cooper announced the no contest.

"I was very frustrated because I wanted to give my fans a great fight and not cheat them," an unmarked Johnson said in his dressing room. "Things happen in boxing. In the heat of battle, you never know what. He hit me low 19 times in four rounds. But it's over. I don't see any reason in fighting him again."

"[Juarez] had been hitting low all night and we told Mark to go to the body," said Ham Johnson, the fighter's father and trainer. "These things happen sometimes."

Johnson had said this would be his last fight at his current weight. He said he still hopes to move up to 118 pounds, and even 122--and bigger paydays. The biggest name among bantamweights is World Boxing Council champion Paulie Ayala. Cedric Kushner, Johnson's promoter, said that Johnson would move up in weight, even to 122 if necessary, rather than retire from boxing out of frustration. "He really should not be denied," Kushner said. For now, Johnson said he would take the best financial opportunity no matter which of the three weight classes.

South Africa's Mbuelo Botile (26-1) won a majority decision over Hector Lizarraga (36-10-5) of Fresno, Calif., in an IBF featherweight elimination match. Two judges ruled for Botile, 99-90 and 96-94, while the third scored it even at 95. The victory moved Botile into possible position to take on the WBC 126-pound champion Naseem Hamed, known as the Prince.

Del Matchett (8-1-1) of Laurel pounded out a unanimous decision over Quentin Williams (10-3) in a six-round junior welterweight match. Matchett was knocked down for an eight count in the second round by a right hand to his right side, which added to Williams's surprise when the decision went to Matchett: 59-55, 58-56 and 58-57.

The undercard began with the beautiful and the bizarre--wrapped into the same scheduled six-round lightweight match. Daniel "The Prophet" Attah, a slick 20-year-old southpaw from Nigeria living in Washington, easily improved his record to 15-0 with eight knockouts by stopping one Domenico Monaco of Naples, Italy a 48-year-old with a 29-37-2 record.

Lawrence "The Crusher" Brooks (3-3) took a split decision over Darrin "Honey Boy" Blichard, who was making his pro debut, in a four-rounder between District welterweights.

Alan Watts (11-5-1) of Washington won a majority decision over Beethoven Scottland (17-5-2) of North Brentwood in a super middleweight six-rounder. James Harris of the District won a unanimous decision in his pro debut over Ruben Romero (2-7) of Tijuana, Mexico, in a four-round flyweight bout.