(CNN) -- He may have knocked out eight-division world champion Manny Pacquiao during their recent bout in Las Vegas but if Juan Manuel Marquez wants a fifth fight against the legendary Filipino he'll need to get permission from his wife.
The Mexican stunned the world of boxing by knocking out Pacquiao in the sixth round of their welterweight contest earlier in December.
It was the first time the 39-year-old has claimed victory in four fights against Pacquiao, who many pundits regard to be the finest pound-for-pound fighter the sport has ever seen.
But with fans clamoring for a fifth bout, Marquez says the only way it will become a reality is if his wife allows him to renege on his promise to retire whatever the outcome of the fourth.
"I made a promise and I know that promises are debts," Márquez said in an interview with CNN en Español.
"I don't see a case to fight again but logically he wants a chance," he added of talk that he and Pacquiao could square off for a fifth time.
Marquez's emphatic victory offered the Mexican some redemption after he failed to win any of the first three fights against Pacquiao.
Their first encounter in May 2004 ended in a draw, while the Filipino took a points victory at the conclusion of their rematch four years later.
But their third clash in November 2011 ended in controversy when Pacquiao was awarded victory in a marginal points decision.
The crowd booed as the judges' verdict was read out and Marquez claimed he should have been declared the victor.
That disappointment made his knockout of Pacquiao, who lay motionless for several minutes after being hit with the decisive blow, even sweeter for the veteran.
"It was a point in my favor because the other fights have ended in controversy but for me this was a clear success," Marquez said. "For me it was a perfect shot -- I think the knockout has been one of the best in a while."
Pacquiao is one of the sport's greats, winning titles at eight different weight divisions. In recent years he's combined his exploits in the ring with a political career in the Phillipines.
His defeat left the country devastated, especially in the aftermath of a super typhoon that devastated parts of the country days before the fight.
Pacquiao's wife was also seen in tears and has since pleaded with her husband to quit. Marquez said he shared her pain having watched a tape of the fight.
"It happened to him now and it could have been me. We are both exposed to this and it made me very sad that Manny Pacquiao's wife was crying," Marquez added.
Pacquiao has now lost two fights in a row after his defeat to American Timothy Bradley in June, though he did make a purse of around $25 million for the fourth installment of his battle with Marquez.
Marquez dedicated his victory to his family, coaching staff, and especially to the president of Mexico, Enrique Pena Nieto.
"I want to dedicate this fight to the new president of Mexico, but with the condition that he handles his duties well," Marquez said.
The 39-year-old had been criticized in some quarters, including on social networking sites, for his support of Nieto, leader of the Institutional Revolutionary Party (PRI).
He said: "I'm no tiny of piece of gold that will be liked by everyone, many people are in one political party, other people are with another, I simply speak as a citizen."
The fighter was fined last October for wearing political propaganda in support of PRI in his third fight against Pacquiao.