Onslow coach Rhys Morgan said they were keen to head back up to determine the winners. "It's a bit disappointing we couldn't finish today but those things can't be controlled," Morgan said, adding as long as the sun shone they would return.
Wellingtonians don't see grass wickets until November, so any game time here is vital to their build up away from artificial pitches.
It's the first tourney Onslow have progressed to the playoff stage, something Morgan put down to having a full-strength side.
They have Brent Arnel as a Firebird player and ex-Cantabrian Matt McEwan from the greater first-class squad in their predominantly young mix.
"Only three players can drive the team bus up in our squad," Morgan said.
In group C, Onslow beat senior team Marewa CC by six wickets on Saturday.
They skittled the composite Napier side for 59 in 18.1 overs, before Andrew Fletcher's 29 runs from 24 balls helped eclipse the total in 11.2 overs.
Marewa's Casey Rangi 2-18 was the best bowler.
McEwan took 3-4, including a maiden, in 1.33 an over, while Jake Bannatyne took 3-9 (2.25).
Onslow beat Complete Flooring Napier Technical Old Boys (NTOB) by 48 runs.
Corey Larsen 38 runs (36) and Arana Noema-Barnett 26 (31) took them to 112-7 before they skittled NTOB for 64, with 15 balls to spare.
In group B, CHB beat Central CC (Rotorua) by seven wickets, with James Mackie 50 runs (36) and Ben Smith 28 (20) helping amass 125-3 in 17.3 overs in reply to Central's 124-9 in 20 overs.
CHB's Charlie Robson took 1-7 (2.33) while Blair Tickner, Nick Blundell and Jake Robson claimed two wickets each.
It was the third time CHB made the playoffs and twice in the final, losing to Heretaunga Building Society Cornwall CC in one of them when the tourney started inviting outsiders from 2011.
"It's disappointing not to get a conclusion but we're glad it's not down to a toss of a coin," Mackie said.
CHB crushed a new-look young Cornwall by 126 runs in the other game, with Smith 120 not out from 60 balls.
"Anything can happen on the day so, hopefully, we'll get some cricket in and have a CHB v Taradale all-Hawke's Bay final," he said.
In group A, Dale beat Havelock North by 65 runs, with captain Luke Kenworthy scoring 44 and Luke Wright 30.
The villagers could only muster 89-9 in 20 overs, with Ruan Markram and Rokon Al Shariar scoring 20 runs each.
Dale then pipped Te Puke CC (Tauranga) by eight runs, with Callum Hewetson scoring 40 runs (49) and Ajaz Patel 27 (28) taking them to 111-7 in 20 overs.
Patel then took 5-23 but Doug Bracewell was the most frugal with 3-14 (3.5).
"We scraped through on net run rate ... we put a lot of pressure into chasing a small target," Kenworthy said, adding it was good tourney and deserved to be finished.
On Saturday, Karori burst the bubble of North Shore CC (Auckland) by 45 runs with Firebird Stephen Murdoch scoring 45 runs (21 balls). Murdoch smashed 70 (35), Alecz Day was 59no (20) and Sole was 46 (19) in humbling The Station Napier Old Boys Marist by 123.