In Rocky III, which boxer defeats Rocky Balboa and takes his heavyweight title?

In Rocky III, Clubber Lang defeats Rocky Balboa and takes his heavyweight title.

Clubber is a powerful contender who believes Rocky has avoided the strongest available challengers. His confrontation with Rocky becomes personal after Mickey Goldmill suffers a fatal heart attack before their scheduled title fight.

Rocky enters the bout emotionally distracted and loses by technical knockout. The defeat marks the end of his long championship reign and exposes weaknesses in his preparation and motivation.

After Apollo Creed helps Rocky rebuild his skills, Rocky faces Clubber in a rematch. The training emphasizes speed rather than simply absorbing punches, and Rocky defeats Lang to reclaim the title. Mr. T played Clubber, making the role his major film debut. The character's aggressive style and distinctive entrance made him one of the series' most recognizable rivals.