Piutau scored one try, set up two others while Louis Ludik, Rob Herring and Jacob Stockdale also scored. Young left wing Robert Lyttle banged over three conversions and a penalty in the first half.
But it was the New Zealand star who just exuded sheer class throughout as Ulster defeated a full-bodied Northampton squad at the Kingspan last night.
Both new boys Piutau, and prop Rodney Ah You, showed what they could bring to the party this season with some early rumbustious charges.
It was a piece of magic from Piutau, that allowed Ulster to take the lead in the 17th minute with a classic mid-air take before Lyttle put Ludik in for the try.
Piutau then finished off some quick-witted work by Paul Marshall whose tap penalty opened up the Saints defence which allowed All Black to crash over in the right-hand corner. Lyttle again added the extras.
A pushover try from a line-out further enhanced Ulster’s lead with skipper Rob Herring getting the touchdown. Lyttle again did the needful with the conversion as Ulster led 24-0 at the break.
With both benches being used at regular intervals the game obviously was a stop-start affair although it was the Saints who scored first on the resumption with prop Alex Waller crashing over.
Then came the other piece of typical New Zealand flair by Piutau .
He broke through from the half way line and although tackled 10 metres out, managed a wonderful back of the hand flip-pass to Stockdale who ran in try number four. Saints did manage to cross the line a few more times with Tom Collins and JP Estelle touching down.
But Ulster no doubt will be the happier.
(Ludik, Piutau, Herring, Stockdale tries; Lyttle penalty, 3 con)
(Waller, Collins, Estelle tries; Myler, Hanrahan cons)
C. Piutau; L Ludik, S McCloskey, D Cave, R Lyttle, B Heron, P Marshall; A Warwick, R Herring (capt), P Browne, F van der Merwe, R Diack, C Ross, R Wilson. Replacements: A Warwick, R Herring (captain), R Ah You, P Browne, F van der Merwe, R Diack, C Ross, R Wilson;
J Andrew, C Black, R Kane, A O’Connor, C Joyce, M Rea, D Shanahan, S Windsor, J Stockdale.
B Foden; K Pisi. L Burrell, H Mallinder, A Tuala; S Myler, L Dickson; A Waller, D Hartley, K Brookes, M Paterson, J Craig, T Wood (capt), J Gibson, L Picamoles.
C Maafu, M Haywood, P Hill, C Lawes, J Ludlam, J Gibson, S Dickinson, N Groom, JJ Hanrahan, H Packman, G Pisi, JP Estelles, T Collins, G Furbank.
L Linton Scorers: