A third fight between boxers signals that their first two bouts produced an exciting victory for each man and that the rubber match is saleable. This is the case for Manny Pacquiao and Erik Morales, as it was for Morales vs. Marco Antonio Barrera.

Morales won the first fight against Barrera, then lost the next two. Against Pacquiao, Morales won a decision, then he was stopped in the 10th round. Because of their styles, Saturday night’s fight at Las Vegas should be another thriller, but it ain’t necessarily so that a rubber match lives up to expectations.

Muhammad Ali’s 14th round victory over Joe Frazier in Manila in 1975 was to my mind the greatest rubber match in the history of boxing, but his third fight against Ken Norton in1976 was a rather dull affair, which is remembered more for the acts of hooliganism in Yankee Stadium that were encouraged by the New York police being on strike.

Frazier had kept the heavyweight title on a unanimous decision in a fight in which he knocked Ali down in the 15th round in 1971 at Madison Square Garden. Neither man was champion when Ali scored a 12-round decision in the Garden three years later. He then became champion again by knocking out George Foreman in 1974 in Africa.

In the Thrilla’ in Manila, the two arch-rivals fought with a ferocity that even left onlookers drained. The fight ended when trainer Eddie Futch would not permit Frazier to go out for the 15th round because Smokin’ Joe could barly see. Futch took his action despite the fact that he thought Frazier was winning. If the fight had gone the distance, however, Ali would have won a unanimous decision.

“You may have seen the last of Ali,” the champion said. “I want to get out of it.” It would have been the perfect time for both him and Frazier to retire.

A third Ali-Norton fight was highly anticipated. In 1973, Norton had broken Ali’s jaw in winning a 12-round split decision. Then Ali needed to win the 12th round for a split-decision victory in the rematch. While some among the 30,298 fans in Yankee Stadium were being mugged, Ali won a close but controversial unanimous decision mainly on the strength of dominating the final three rounds.

While the third Ali-Norton bout was marred by violence outside the ring, the third Emile Griffith-Benny “Kid” Paret match will always be remembered for violence inside the ropes.

At the weigh-in for the fight at Madison Square Garden on March 24, 1962, Paret, the defending welterweight champion, made some remarks about Griffith’s sexual orientation and touched him on his bare back. That night, Griffith, who was far ahead in the scoring, pinned Paret in a neutral corner and landed about 25 hard punches before referee Ruby Goldstein intervened. Paret slumped to canvas and did not regain consciousness. He died nine days later.

Two rubber matches that will always be overshadowed by the second fights were Floyd Patterson against Ingemar Johansson and Riddick Bowe against Evander Holyfield.

The last Patterson-Johnansson fight in 1960 at Miami Beach, Fla., probably was the best of the three, with Patterson being knocked down twice and the Swede once in the first round before Patterson scored a sixth-round knockout. Mention Patterson-Johansson, however, and the first fight that pops into mind is the second one in which Patterson became the first man to regain the heavyweight championship when he knocked out Johansson in the fifth round at the Polo Grounds in New York City. Johansson had won the title a year earlier by knocking down Patterson seven times in the third round and stopping him.

Evander Holyfield and Riddick Bowe could have fought 10 times, and their second would still be the one most remembered. In the seventh round of that fight in 1993, Fan Man crashed into the ring ropes, causing a 21-minute delay. Holyfield would regain the undisputed heavyweight title on a 12-round majority decision. The two men would be former champions when Bowe won the rubber match on an eighth-round technical knockout in 1995.

A rubber match that was an afterthought was Sugar Ray Leonard’s one-sided decision over Roberto Duran for the WBC super middleweight title in 1989, nine years after one of the most controversial fights in history. In 1980, Leonard regained the WBC welterweight title from Duran when the Panamanian quit in the eighth round. It was the “No Mas” fight.

Action was packed into almost three rounds of the rubber match between Tony Zale and Rocky Graziano, but still the bout paled in comparison to the first two fights, which were as intense as any two bouts in boxing history. Zale took a beating before knocking out Graziano in the sixth and retaining the middleweight title in 1946. Graziano took an even a worse drubbing before rallying to top Zale in the sixth round and win the championship in 1947.

In their third match at Newark, N.J., in 1948, the 26-year-old Graziano, nine years younger than Zale, was a 12-5 favorite, but Zale was in charge from the outset as he become only the second man to regain the middleweight title, joining Stanley Ketchel, who did it with an eighth-round knockout of Billy Papke in 1908. Zale knocked down Graziano in the first round and knocked him down again in the third before knocking him out.