On June 19, 2002 Siaki debuted on the first TNA pay-per-view as one-third of The Flying Elvises with Jimmy Yang and Jorge Estrada. The Elvises were a comedy heel stable who impersonated Elvis Presley. The Elvises eventually split, with Siaki defeating Yang in a singles bout on August 21, 2002. Siaki now heel, went on to joined Vince Russo's Sports Entertainment Xtreme a faction that tried to take over TNA. There he was then given a valet, Desire, a fellow TCW graduate, and earned the nickname "The Ace in the Hole".
On December 11, 2002 Siaki defeated Jerry Lynn for the TNA X Division Championship. He held the belt until February 12, 2003 when he lost to Kid Kash. In July 2003 Siaki began a feud with D'Lo Brown, who he defeated in a Casket match. In October 2003 he formed a tag team with Ekmo, which split when Ekmo began working for All Japan Pro Wrestling. Siaki eventually became a face, and in April 2004 he and Simon Diamond began feuding with Glenn Gilberti and Johnny Swinger. After Siaki and Diamond were victorious in a tag match, their opponents were forced to wear Irish and Samoan native dress respectively, punishing Gilberti and Swinger for the ethnic jokes they had made in the preceding weeks.
Siaki formed a tag-team with Apolo. At TNA Lockdown 2005 he and Apolo defeated Lance Hoyt and Chris Candido in a steel cage tag match. Candido died four days after this match due to a blood clot brought on by a broken leg he suffered in the match. Throughout mid-2005 Siaki and Apolo feuded on a casual basis with The Diamonds in the Rough. In December 2005, Siaki's contract with TNA expired, and he declined to re-sign, instead leaving the promotion on good terms.
In late December 2005, Siaki signed a contract with World Wrestling Entertainment. He debuted in the WWE developmental territory Deep South Wrestling on February 2, 2006, suffering a minor injury in the process. On February 23, 2006, Sonny returned to Deep South Wrestling as a heel having a match with Damian Steele. Going by the moniker "Cocky Siaki", he and Eric Perez (as Urban Assault) would win the Deep South Tag Team Titles on November 30, 2006. He then began teaming up with Afa Anoa'i, Jr. Both Siaki and former partner Eric Perez were working Raw house shows in March but Siaki suffered a back injury during that tour which left him out of action for 1 month. Siaki continued to tag with Afa Jr. in Deep South until it closed in April 2007.
Siaki then re-debuted with Afa, as The Samoan Fight Club, in the new development territory, under the World Wrestling Entertainment (WWE) name, Florida Championship Wrestling. On September 15, 2007, it was reported that Siaki had been released from his developmental contract. Three days after the release, Siaki issued a statement saying that he has had some "personal issues" at home and that his focus was on his family right now, not wrestling.
On September 17, 2008, Siaki retired from professional wrestling.
- Deep South Wrestling Tag Team Championship
- Great Championship Wrestling Heavyweight Championship
- Great Championship Wrestling Tag Team Championship
- Independent Professional Wrestling Alliance North American Championship
- National Wrestling Alliance Wrestle Birmingham Tag Team Championship
- Swiss Wrestling Federation Powerhouse Championship
- TNA X Division Championship
- Turnbuckle Championship Wrestling Tag Team Championship