The second saw Ngatai slice through to hand fullback Kurt Baker a try in his 50th game.
Two desperate sides produced a stinker of a first half.
Highlights: Taranaki v Counties-Manukau
In case you had doubts about that, even referee Nick Briant told both sides before the break that there had been "some pretty average rugby."
It rained in New Plymouth and there was a plethora of collapsed scrums, pushed passes, dropped ball, bad tap-downs and plenty of niggle.
Briant almost blew the pea out of the whistle, but he mostly had good cause.
Steelers No 8 Maama Vaipulu was, however, harshly sinbinned after he appeared to have ripped the ball free late in the first spell.
Counties Manukau never really looked likely, other than a late try to Vaipulu, and it did not help when first five Piers Francis was concussed.
Hika Elliot, the No 4 hooker in the nation, came off the pine at halftime for his new province Taranaki. He was accurate with his lineout throwing and involved around the park.
Last season both unions fought to a similarly dour 9-9 stalemate the same venue to kick off the season. Little did we know then that Taranaki would go on to be Premiership winners.
Both teams are back in action this Sunday on a short turnaround. Counties Manukau host their Chiefs cousins Bay of Plenty, while Taranaki are at Northland.
Taranaki 17 (Seta Tamanivalu, Kurt Baker tries; Codey Rei 2 con, pen) Counties Manukau 10 (Maama Vaipulu try; Jared Page con; Piers Francis pen) Halftime: 3-3