However, Diack pointed out veteran Liam Rukuwai, who is returning from injury and unavailable for Bay selection, was the pick of the bowlers.
Rukuwai took 1-10 from 13 overs, including nine maidens.
In reply, last season's overall champions overhauled the target with 90-3 in just 13 overs.
In-form NTOB batsman Indika Senarathne provided the platform at No4 with an unbeaten 51 after opener Josh Paerau scored 22.
On the adjacent No1 wicket, Heretaunga Building Society Cornwall CC had to settle for a winning draw against The Station Napier Old Boys' Marist (NOBM).
The hosts posted 262-6 in 55 overs with leftie Scott Brocklehurst scoring a patient 60 from 114 balls and fellow opener Ben Wilson adding a quicker 43 runs (60).
But it was No3 Jayden Wiggins who scored a quick-fire 62 runs from as many balls before Nathan Waites backed up with 43 not out.
For NOBM, Mason Baker took three wickets and Brendan Quinn two but the pair haemorrhaged too many runs.
In defending the total, Cornwall were unable to mop up the NOBM who were 189-8 in 55 overs.
No8 Anoop Renuka-Prajad scored a brisk 55 from 72 balls while No6/veteran Daniel Drepaul dug his toes in to stop the rot with 38 (108 balls) to help deny the hosts an outright victory.
Wiggins snared 3-42 from 17 overs, including six maidens, while Eamon claimed 3-33 from 12 overs.
Cornwall player Graeme Hodges lauded his young batsmen, Wiggins and Wilson for their knocks as well as Wiggins and Corbett for bowling in the right channels to claim 10.6 points.
"The club is celebrating its jubilee [25 years] on Friday so any past members or associates are welcome to buy tickets.
"We'll be spinning some old yarns, looking at the future and celebrating the past," Hodges said.
At Forest Gate Domain in Ongaonga, defending champions Ruahine Motors Ford Central Hawke's Bay CC (CHB) beat Sharpies Driving Range Taradale CC by eight wickets.
The visitors managed 172-5 in 47 overs with No5 Matt Nelson 57 not out from as many balls while Connor Underhill did everything to stay in for 32 (82 balls).
CHB bowler George MacPherson took 2-42 against his old club but Jack Wakeling was the most frugal with 1-12 in nine overs, including five maidens.
"The two Medley Station boys started off things very well for us," captain James Mackie said.
"The younger boys put their hands up today," Mackie said after openers Will Harker scored 45 runs from 45 balls and George Larson contributed a patient 57 not out from 120 deliveries.
Wakely chimed in with 32 (44) and Mackie was unbeaten on 31 (28).