Unbeaten Sugar Ray Leonard continued his string of victories today with a technical knockout over Tony Chiaverini, who failed to answer the bell for the fifth round in Caesars Palace.

Although it appeared the referee stopped the bout after examining an inch-long gash under Chiaverini's right eye, the boxer said later his corner tossed in the towel.

"They didn't want to see me get broken up by continuing," said the 26-year-old Kansas City fighter. It goes into the books as a fourth-round knockout.

Leonard, 23, from Palmer Park, Md., appeared to get angry with his opponent in the pivotal fourth round, after scoring consistently in the early going with a lightning left jab.

Leonard, the Olympic Gold medalist as a junior welterweight in Montreal in 1976 fighting today at 151 pounds came out of his corner with a flurry of punches and Chiaverini, appearing unhurt at that point, maneuvered and held Leonard in a neutral corner and began punching at Leonard's midsection.

Leonard, now 23-0 with 14 knockouts, attempted to get free of the corner ropes, but was held there by the strong arms of the southpaw Chiaverini. After the referee separated the two contestants, Leonard swiveled his hips mockingly and said "come on" to Chiaverini.

Leonard, took aim with his left hand, first opening the wound and then nearly closing the eye by the round's end.

Chiaverini, 153, said he was not surprised by Leonard's speed but said "he hits a little harder" than anticipated.

"He also caught me with a good one in the throat," said Chiaverini, now 30-4-1 after coming into the ring the World Boxing Council's sixth-ranked superwelterweight (junior middleweight).

Leonard said Chiaverini "put up a great fight" and called him a "top-caliber fighter."

He said he did not make the mistake of looking toward his Dec. 1 WBC welterweight title match with Wilfredo Benitez of Puerto Rico. That bout will be televised nationally by ABC from a site to be determined.

Leonard earned $140,000 today; Chiaverini $61,000 for his 12 minutes of boxing. CAPTION: Picture, South African heavyweight Gerrie Coetzee heads for corner as Leon Spinks sprawls against ropes. It was one of three times the ex-champ was floored in the first round.