"I finished him in the first round and I have finished the No2 in the first round.
"I'm not cocky, but I'm confident."
Asked about fighting older men, he said: "Because of my weight, I have to fight men. There aren't many 15-year-olds that are 117kg."
The finishing touches on his preparation were provided by Parker's trainer Kevin Barry at the open-sided gym on the outskirts of Apia constructed in an abandoned building by Lika's father, who became known as "Inga the Winger" during his rugby career, and his elder brother Bubba, who is also fighting at the nearby Faleata sports complex on Saturday.
Parker, who did a light session at the gym today, features on a poster positioned between pictures of former Samoan heavyweights David Tua and Jimmy Peau.
Barry helped Lika with his footwork and jab, and afterwards said: "He's a very exciting young prospect. To have that size and that power at the age of 15 is quite unique. He obviously has very good pedigree and I saw huge potential in the short session that we did."
Lika's ultimate goal is to become a professional fighter, but first he has high hopes as an amateur.
"We have a five-year goal that my dad and I have set and the biggest goal is the last year, the 2020 Olympics, that's the aim," he said.
Tuigamala senior, a blockbusting runner who scored five tries in 19 tests for the All Blacks before playing 22 tests for Manu Samoa, said of his youngest son: "He's been training for three years with his older siblings so he's been dying for this opportunity and I said 'what better way than fighting on Joseph Parker's undercard'."
Tuigamala, based fulltime in Samoa after several failed business ventures in New Zealand, said boxing came naturally to all his four children.
"This is the sport they wanted to do and so I'm very honoured to be able to do something to support them as a father. Unfortunately my father died when I was only 10 years of age so I never had the privilege of having my dad around. I made a promise to my kids that whatever sport they chose I'll always be there and that's been the case since they were young."