Carlos Monzon vs Rodrigo Valdes II

On July 30, 1977, at Monaco's Stade Louis II, Carlos Monzon made his final ring appearance, securing a unanimous decision over Rodrigo Valdes to retain both the WBC and WBA middleweight titles. The fight marked a dramatic end to Monzon's championship reign, which had begun in 1971.

Valdes, who had lost their first encounter despite his brother's tragic death days before, entered as the aggressor. The Colombian challenger, weighing 158 pounds to Monzon's 159, shocked the champion in round two with a right cross that sent Monzon to the canvas - only the second knockdown of his career.

The early rounds belonged to Valdes, who dominated through the first seven frames. The fight's momentum shifted when Monzon opened a severe cut above Valdes' left eye, requiring immediate hospital attention post-fight. This injury proved decisive, as Monzon controlled the latter half of the contest.

The judges scored it: Roland Dakin 144-141, Angelo Poletti 145-143, and Kurt Halbach 147-144, all for Monzon. The Associated Press scored it slightly closer, 145-144, for the champion.

Monzon, earning $500,000 to Valdes' $150,000, announced his retirement immediately after his 14th successful title defence: "I think I showed everyone I'm one of the great ones. But it's over now. For sure. I'm going to start living like a human being tonight."

Valdes' manager, Gil Clancy, attributed the loss to the eye injury: "It was the cut that did it. Valdes was winning before he was cut. No doubt about it. That was the turning point."

Monzon retired with a record of 86-3-9 (59 KOs). He was inducted into the International Boxing Hall of Fame in 1990 and died in a car accident in 1995. Valdes (59-5-2, 40 KOs) continued boxing until 1980 and passed away in 2017.