"The first 70 minutes we dropped ball, kicked good possession away," said Pirates coach Phillip Morris. "And that's not taking away from how good [Utiku] played. It's high risk, high reward."
He praised Ulukuta and Tyrell - the captain's barnstorming second try where he ran right over four defenders was the decisive blow.
"You've got to have an 8, 9 and 10 that are experienced. They know how to step up."
Utiku coach Gavin Thompson said his team just ran out of legs.
"We haven't got a bench, that's what it comes down to.
"No disrespect to the guys on the bench, but they'd already played for the Bs."
It is a conundrum where the very thing that put Utiku so far ahead - confidence to run it from their own danger zone - also undid them when Pirates finally managed to apply pressure - but Thompson said he would not reel them in.
"That's the brand of rugby that we're playing this year and hopefully it will come off more times than it doesn't."
Utiku chased hard right from the kickoff - with Volau looking to impose himself.
Yet Pirates scored first against the run of play as Takavesi made a long dash, finding Stowers, with play swinging back to the other sideline for prop Brett Turner to score.
Utiku were always threatening from the midfield, especially after Pirates lost flanker Brad Mathews to the sinbin for a late clean-out at the ruck.
New Pirates winger Denaia Ulukuta got through a lot of work clearing his team's dangerzone, while Utiku's Kubunavanua, Nabuliwaqa and centre Willy Hirini produced some heart-in-mouth stuff with busts and pop passes which left Pirates scrambling.
Finally, just before halftime, a Nabuliwaqa burst set play wide for Volau to cross, then just after the break Kubunavanua scorched through and made a lovely flick to flanker Matt Crawford, who found Landridge to score out wide.
The teams traded penalties for 15-10, before Ulukuta went over to tie the match after sustained pick-and-go raids, following Utiku being penalised for not releasing.
Pirates halfback Ricky Boniface scrambled to save a loose kickoff but Volau got the clearing kick and smashed straight through four tackles, finding Nabuliwaqa on his shoulder with all the gas to score.
Wanting in on the action, Utiku's forwards took a penalty lineout and drove Shaw over in the corner for 29-15, as first-five Ricky Alabaster found his kicking form.
But Pirates responded, shutting down another Utiku breakout and spreading to the left for speedy reserve Edward Emana to cross untouched, as Lasa Ulukuta suddenly took over the game.
Nabuliwaqa was sinbinned for a professional foul at the worst moment for his team, and after another series of hit-ups, hooker Manulua Lafi backed himself despite support outside and dragged the defenders over the line for 29-29.
Lasa Ulukuta then ran right through the middle of Utiku and over the top of Kubunavanua for their third try in six minutes.
Pirates still were not done with time running out as Lasa Ulukuta freed his arms to centre Saena Vili going under the posts - then Tyrell was downright audacious as he batted along a pass inside his own 22m for Vili, reserve Josia Dawai and Takavesi to sweep right to the other end for their seventh try.
