Onerahi's Henry Cooper stole the show at Kensington Park as he scored a mature 83 to set his team up for victory over City.
Cooper's masterful innings was supported well by the ever-reliable Dewayne Bowden, scoring 28, in steaming hot one-day cricket conditions.
Onerahi were eventually all out for 212 in Saturday's match, with Kieran Nelson bowling tidily for City on his way to picking up three wickets.
In reply, City made a good fist of it as Chris Page top-scored with 51 runs and was well supported by Jamie Morgan, who scored 39.
However, thanks to some accurate bowling from Adam Sylva and Tom Herman, both of whom picked up three wickets, City fell 38 runs short.
Kaipara Flats ran away with their match as they destroyed Kamo on a good, hard wicket at the Kamo Recreation Ground.
Bowling first, Kaipara dismissed Kamo for 112 with Keith Bond proving the main strike weapon as he picked up 5 for 25.
Only Logan Miller, batting at nine, made any substantial contribution for Kamo, with his 27. Bond was well supported by Kyran Dill, who picked up three cheap wickets.
Kaipara then wasted no time in knocking off the required runs as Brad Wilson slammed the Kamo bowlers to all parts, scoring an unbeaten 72 as Kaipara took the match out with only one wicket down in the 27th over.
Maungakaramea schooled the previously in-form Zest Insurance Whangarei Boys' High School team at home on a wicket which offered some initial assistance to the bowlers.
Maungakaramea's Cody Andrews proved simply too good as he accounted for six of Boys' High's batsmen for only 11 runs.
Andrews' 6 for 11 was a bowling master-class as the Boys' High players had little answers to his pace and movement, Boys' High being bowled out for 93, with John Child top-scoring with 28.
In reply, Maungakaramea were in all sorts of trouble early on at 34 for 6, and then 60 for 7.
Nick Stobart and Tim Anderson were in fine form for Boys' High as they put Maungakaramea under pressure.
However, Maungakaramea managed to limp home with seven wickets down in the 34th over.