The chance of a comeback began to slip from Pikiao's grasp early in the second half as Mangakino continued to find the try line and race out to a 32-0 lead.
Pikiao finally got on the scoreboard in the 60th minute, through hooker Zane Hay, but it was too little too late. Mangakino scored two more tries to make it 40-6 before Pikiao scored a consolation try through fullback Quentin Ryan on halftime.
Mangakino captain Johnson Peri said the game was "full of positives".
"We came here with a plan, which was to have some structure and play to our strengths - I think it worked out well," Peri said.
He said the Mangakino players were feeling as confident as they looked.
"We've got some quality players and coming off the back of the Bay nines tournament and the Bay 13s it has been nothing but positive. But we knew the pre-season results didn't matter if we didn't perform today.
"As we progress, everything behind us we leave there and try to concentrate on what's in front of us."
Pikiao coach Jason Parata said the majority of his players' efforts were good, they were just not consistent enough.
"We were good for four tackles of every set, we just need to get good at six tackles of every set. It's amazing what one missed tackle does, or a repeats set or a couple of penalties for not playing the ball properly. It's all those little things," Parata said.
Rikihana Te Rangi has been selected to captain Pikiao this year and the big forward was one of the standouts for Pikiao, running hard to the last minute.
"He got a lot of confidence out of everything that happened last year, winning the final and playing for Bay of Plenty. He's talking a lot more in warm-ups and trainings and he'll lead from the front."
Bay of Plenty/Coastline Premier Rugby League results
Taupo Phoenix 20 v Papamoa Bulldogs 12
Pacific Sharks 42 v Ngongotaha Chiefs 28
Mangakino Hawkes 40 v Pikiao Warriors 10
Otumoetai Eels, Bye