Guest player George Slefendorfas scored two in the first half for Canterbury.
Auckland City opened the scoring in the 23rd minute when David Mulligan hit a stunning 25m rocket into the bottom-left corner of Neil Mouncher's goal.
Within 15 minutes the predominantly young home side were back on terms when Sam Campbell clipped former City player Adam Thomas to give away a penalty.
Captain courageous Thomas hit home from the spot for 1-1.
The second half belonged to City's international connection as livewire Spaniard Manel Exposito and Argentine Emilano Tade, in his first premiership outing for the Aucklanders since his off-season switch from Team Wellington, scored two each.
The win sent an early warning to other teams and was an ideal first-up showing despite Auckland being without injured captain Ivan Vicelich, Adam Dickinson and Spanish midfielder Andreu Guerao.
Waitakere, too, looked useful in their win over a Hawkes Bay side forced to make changes with the absence of key players.
While enjoying the advantage in territory and possession, Waitakere needed 41 minutes to take the lead when captain Jake Butler provided the finishing touch to Allan Pearce's strong lead-up on the right.
A change of tactics and personnel by Bay coach Matt Chandler at the break forced the hosts to play deeper in the second half and Waitakere did not add to their halftime lead until the 79th minute, when Pearce pushed home the rebound after his penalty attempt had been blocked by Richard Gillespie.
Four minutes later Roy Krishna made certain of the points when he walloped home from close range after getting on the end of a good ball from substitute Sean Lovemore.