One of Muhammad Ali's greatest fights took place in Kinshasa on October 20, 1974, when he challenged George Foreman for the world heavyweight title.
Ali was 32 years old by then and, despite his typical pre-fight bravado, he appeared to have little chance against a 25-year-old world champion at the peak of his powers.
Foreman entered the ring unbeaten in 40 fights as a pro, and great boxers such as Joe Frazier and Ken Norton had failed to last two rounds against him in recent fights.
Foreman dominated the early stages of the bout... click on the video above as veteran boxing writer Colin Hart takes you through what happened next.