Magasiva had his start on television during the 1990s, beginning with comedy. In 1999, he portrayed Mason Keeler in "Jackson's Wharf". In 2001 he starred in his first major film," Stickmen", and joined the Naked Samoans. In 2002, he played Mauhúr in Peter Jackson's "". He returned to television in the show "The Strip", continued his work with the Naked Samoans, and made a minor appearance in "Power Rangers: Ninja Storm", also starring his brother Pua as the brother of Pua's character of Shane Clarke. In 2006, Magasiva co-starred in "Sione's Wedding", a comedy film that achieved commercial success in New Zealand. In 2007 he co-starred in the horror film "The Tattooist".