In January 1986, Afi signed with the World Wrestling Federation (WWF), making his debut on January 23 at a house show in Anaheim, California in a win over Tim Patterson. He would later make his debut on Prime Time Wrestling, where he was billed as "'Superfly' Afi", and deemed to be the cousin of Jimmy Snuka. On the March 8 episode of The Body Shop, Afi was introduced to viewers of WWF All Star Wrestling as Snuka's cousin. Afi was undefeated initially, albeit against lower level competition such as Rene Goulet, Barry O, Ron Shaw, and Matt Borne. On March 6, 1986, he gained his first significant victory when he pinned Bret Hart at a house show in Buffalo, New York.
Afi's undefeated streak ended three days later when he lost to Hart's partner Jim Neidhart in Landover, Maryland, but he continued to be pushed. Afi gained victories in April over Hercules Hernandez and Paul Roma. However, fans were unaccepting of Afi as the replacement for the departed Jimmy Snuka, and openly heckled him in matches. He began to slide down the card, losing that spring to Bret Hart, Don Muraco, and Jake Roberts. By the summer, all momentum had ceased. Now billed as Sivi Afi, he became a near enhancement talent and lost to the likes of Bret Hart, Randy Savage, Harley Race and Ted DiBiase. In the summer of 1986, he formed a short lived tag team with King Tonga, but the duo was generally unsuccessful.
Afi entered 1987 firmly established as an upper-level enhancement star, losing regularly to Hercules and others but continuing to gain victories against other opening-level talent such as Frenchy Martin and Terry Gibbs. He was used frequently as a substitute when other wrestlers could not make house shows, teaming with others such as Raymond Rougeau. In the summer of 1987, he entered a lengthy losing streak, falling to preliminary competition such as Steve Lombardi and Frenchy Martin. Following a loss to Ted DiBiase on December 9 at a Wrestling Challenge taping in Fort Myers, Afi went on a hiatus.
In 1988, after teaming for a short time with Haku as one half of The Islanders, he also wrestled in six-man tags with the original Islanders, Haku and Tama. He debuted a new gimmick, that of "High Chief Afi", a Samoan chieftain. As part of his gimmick, Afi had gotten his legs and abdomen heavily tattooed (ala High Chief Peter Maivia). Unfortunately for Afi, it was all for naught; Tama would shortly thereafter depart from the WWF and Haku was repackaged as "King Haku" to replace the injured Harley Race, leaving Afi without a team or manager. His last match came on August 27, 1988 in Burlington, Vermont against SD Jones. Afi left the WWF soon after.