[4] Mann attended Kelston Boys High School and played for the Glenora Bears from schoolboys right up to premier grade.
When the Tonga national rugby league team was first formed to compete in the 1986 Pacific Cup he was selected to play in the side, making his international début.
Mann played for Warrington as a hooker in their 14-36 defeat by Wigan in the 1990 Challenge Cup Final at Wembley Stadium, London on Saturday 28 April 1990, in front of a crowd of 77,729.
Mann played hooker in Warrington's 12-2 victory over Bradford Northern in the 1990–91 Regal Trophy Final at Headingley, Leeds on Saturday 12 January 1991.
Mann was signed by the Auckland Warriors who were to enter the Australian Rugby League competition in 1995, and played in the club's inaugural match.
[15] In 2024, Mann was drafted in to make his debut on episode 2 of Match Fit: Union vs. League as a medical substitute for Henry Fa'afili, who pulled out before the bronco test due to atrial fibrillation.