While the Barretts lined up for Taranaki, Sam Cane made his return from injury for the Steamers at the back of the scrum, with a characteristically strong performance in the contact areas and around the breakdown.
However, it was new All Black Vaa'i who made the biggest impact of the national team's players. The young lock displayed his talents with ball in hand, rampaging up the middle, shrugging off defenders, breaking the line and scoring tries.
Vaa'i got the scoring going early for the hosts, but their lead didn't last long as former Taranaki halfback Te Toiroa Tahuriorangi hit back for Bay of Plenty less than 10 minutes later.
The sides continued trading tries throughout the first half – each scoring three tries each in the first 40 minutes, but Taranaki held a five-point lead at the break thanks to the boot of Jordie Barrett.
Replacement five-eighth Otere Black narrowed the gap to two with an early penalty in the second half, but with Vaa'i and Jordie Barrett the next to cross the stripe Taranaki's lead was too much for the Steamers to run down.
Elsewhere, Northland overcame an early 17-point deficit to topple Manawatū 43-26 in Whangarei.
Manawatū scored two early tries on their way to a 20-3 lead after 20 minutes, but they had little more to show for their work in the game.
However, the biggest upset of the round was saved until last, with Southland stunning Hawke's Bay, 16-10. In a game perhaps best summed up by all four tries being scored by hookers - Greg Pleasants-Tate and Ash Dixon both grabbing doubles - Southland came back from 10-6 down at halftime to cross twice in the second half and hold on for victory in cold conditions.
Southland, who only last season broke a 27-game losing streak and were installed at $101 outsiders to win the Championship, even had to call up 42-year-old local legend Jason Rutledge after injuries in pre-season, with the reserve hooker helping to win a late scrum which sealed a victory in his 140th game for the province.
Taranaki 36 (Tupou Vaa'i 2, Penalty try, Ricky Riccitelli, Jordie Barrett tries; Jordie Barrett 3 cons, pen) Bay of Plenty 29 (Keepa Mewett, Te Toiroa Tahuriorangi, Emoni Narawa, Fa'asiu Fuatai tries; Dan Hollinshead 2 cons, Otere Black con, pen). HT: 24-19
Northland 43 (Sam Caird, Sam Nock, Kara Pryor, Sam McNamara, Jordan Olsen, Rene Ranger tries; Wiseguy Faiane 4 cons, Daniel Hawkins con, pen) Manawatū 26 (Sam Stewart, James Tofa tries; Ben Wyness 2 cons, 4 pen). HT: 22-20