For a long period, though, North Harbour dared to dream. They had much the better of the last 15 minutes of the opening stanza, scoring through second-five Michael Little, who showed his wide range of skills and competed hard at set-piece and in the loose.
Hawke's Bay, so dominant early, went to sleep. They took some poor options, were penalised heavily by referee Glen Jackson in his last outing before RWC and were pressured by the challengers.
If Daniel Halangahu had brought his kicking boots, as he did against the Stags six days earlier, North Harbour would have led at halftime rather than facing a five-point deficit. But he left 11 points on the track.
The Harbour backs looked much better than they have done in 2015, passing well and running good angles and teenaged No 8 Hapakuki Moala-Liava'a was a handful on the charge. But defence was an issue for the team as a whole.
No 8 O'Connor had a blinder in his 100th first-class game and scored a try off a sweetly-timed short ball by lock Mark Abbott.
Israel Dagg ran freely and effectively from fullback, and scored a try after a Magpies' counterattack.
The star turn in the backs, however, was No 10 Ihaia West, a man who missed Maori All Blacks selection and endured a challenging Blues season, but he showed his value as one of the country's best goalkickers with eight from eight, a pinpoint crosskick for Richard Buckman's try and a rare strip on an opposition forward.
The Magpies moved past Waikato into third place on 59 - behind Auckland and Canterbury - on the all-time list of Shield victories since 1904, and have chalked up nine successful defences in this tenure.
They travel to Canterbury next Saturday for a crossover clash, and North Harbour return to Albany to host Counties Manukau. The Magpies' next Shield defence is on September 19 against another Championship side in Bay of Plenty.
Hawke's Bay 48 (R. Tongia, I. Dagg, R. Buckman, B. O'Connor, A. Dixon, C. Eaton tries; I. West 6 cons, 2 pens)
North Harbour 32 (T. Li 2, M. Little, J. Manihera tries, penalty try; D. Halangahu con, pen, M. McGahan con).
Halftime: 20-15