City were never really in the chase after losing early wickets but took their revenge by batting out the rest of their 20 overs to finish the day as the only team not to register a win.
Kaipara will field the same side next Saturday minus James Marshall, who is available for Sunday morning's fifth round match - and for the afternoon's final - if Kaipara qualify.
Zest Insurance Boys High School started their season with a morale-boosting victory over City in the morning.
BHS reached 151/8 in their 20 overs with all of their batsmen contributing, with City professional Zack Khawaja taking 3/19. City were quickly behind the required run rate, and only scored 80/7 in their 20 overs.
In the other morning match Maungakaramea beat Onerahi with a good display of bowling, limiting them to a meagre total that Maungakaramea chased down easily.
Onerahi-Central bounced back to beat BHS in the afternoon with a good bowling display.
BHS put on 33 for the first wicket before the bowlers, led by Henry Cooper (3/12) and BJ Howe (3/24), had them all out for 77.
Onerahi made heavy work of their chase with left arm spinner David Armitt taking 2/18 and then Glamorgan import Jack Murphy taking a couple more to have the match in the balance at 49/6. Dillion Lees (19no) and Michael Vickers combined to steer Onerahi home in the 19th over.
Kamo upset Maungakaramea in the other match with Ben Hyde's fighting 77 helping them reach a defendable total of 112. Right arm medium bowler Jason Prowse put the brakes on the chase with a couple of top order wickets.
The competition continues next week with two rounds on Saturday with the fifth round on Sunday morning followed by the final on Sunday afternoon.