Although champion Jose (Pipino) Cuevas is Angel Espada's next opponent, Espada and the rest of the welterweight division are haunted by the specter of Sugar Ray Leonard, according to Espada's manager.

Espada and World Boxing Association title-holder Cuevas will tangle for the third time Oct. 20 at RFK Stadium. The two signed the contract yesterday for the first title bout in Washington since Joe Louis defeated Buddy Baer at Griffith Stadium in 1941.

Felix Zabala, Espada's manager, was thinking more of Leonard yesterday. Jim Denson, the copromoter of the October fight, announced that both Cuevas and Espada had consented to return here to face Leonard should Leonard win his Dec. 1 title bout with World Boxing Council champion Wilfredo Benitez.

Zabala does not like Benitez's chances.

"It will be an easy fight for Leonard," Zabala said. "Benitez cannot punch, although he is an excellent boxer. But, if you cannot punch how are you going to stop Leonard?"

The welter weight division has become both the classiest and most compeititive in boxing. The 21-year-old Cuevas (25-3) won the title three years ago from Espada (47-8-1). Benitez is undefeated, as is Leonard. Former lightweight champ Roberto (Stone Hands) Duran wiped out that division and has moved up to welter; he has lost only one bout in 13 years. The No. 4-ranked contender is Tommy Hearns, who is also unbeaten and has trouble getting a bout with any other top contender.

However, Zabala thinks Leonard stands alone.

"Pound for pound, Leonard is the best there is," Zabala said. "It would be easier for us to take Duran than Leonard. Duran comes to fight; he's right there for you. Leonard is entirely too quick, much too hard to find."

What about Leonard against Duran?

"I like Leonard over even Duran," Zabala said.

Cuevas, a Mexico City native, has beaten Puerto Rican Espada twice, with the referee stopping the proceedings both times.

Both fighters are considered sluggers. The 31-year-old Espada has knocked out 29 of his 47 victims; Cuevas 22 of 25. Cuevas began fighting professionally in Mexico at the age of 14 and he suffered two losses his first year, neither of which is counted on his advertised record.

The 15-round main event highlights the first boxing program ever at RFK. Four bouts make up the undercard.

Johnny Gant, a victim of Espada by decision in a title bout in 1975, faces Jose Palacios of Mexico City in a 10-rounder. Philadelphia's 36-year-old, bald-pated Bennie Briscoe takes on Mexican champ Marcos Geraldo of Sonora in a 10-round middleweight bash. In an eight-round junior featherweight fight, Derrik Holmes of New Carrollton, Md., will try for his 10th victory against one draw over an opponent to be announced.

A fifth bout involving heavyweights is scheduled, with combatants to be announced. Denson is reportedly seeking retired Dallas Cowboy defensive end Ed (Too Tall) Jones, who announced he would become a boxer earlier this summer.