By the end of November he had won five times, defeating Simon Zondo and then Mose Mthiyane on fourth-round knockouts.
In March 1983 Mitchell won an eight-round decision from Jerome Gumede, earning him a South African junior-lightweight title shot at Chris Whiteboy.
Morake faced Mitchell for the third time in March 1984, and the champion again defended his South African title over 12 rounds.
Mitchell won on a twelfth-round KO, but Morake had absorbed a terrible amount of punishment and later died of head injuries.
In June of the same year, he defended his South African junior-lightweight title against Bushy Mosoeu, winning on points over 12 rounds.
In September he was given a crack at Alfredo Layne's world junior lightweight title in Sun City, South Africa.
Mitchell seized his chance, dropping the Panamanian champion three times in the tenth round to win the title by knock-out.
On 31 July, he faced Francisco Fernandez in Panama City and, with his excellent conditioning to the fore, knocked out the challenger in the fourteenth round.
In 1991 Mitchell travelled to Sacramento to face local hero Tony "The Tiger" Lopez arguably the toughest foe of his career.
However, he again faced Lopez in Sacramento in September, and on that occasion made sure of victory with a convincing points win, claiming the IBF title in the process.