Wanganui were bowled out for 154, with Joe Redpath (51), Adam Boult (39) and Sam Beard their best contributors, while BoP bowler Luke Taterly picked up 3-21.
In reply, BoP had enough deliveries remaining but were losing wickets and succumbed within one scoring shot on 149 with three overs left.
Beard (3-20), Angus Dinwiddie (3-27), James Pennefather (2-20) were the pick of the bowlers.
Wanganui made the clean sweep with a three wicket win over Invitational yesterday morning.
While Invitational's Andrew Mackintosh scored 51, they were bowled out for 167 with Dinwiddie picking up 3-27.
Wanganui reached 168-7, helped by a well-compiled 56 retired from Matthew Simes, making a 180 degree flip in form following two ducks.
BoP booked their place in the 40-over final with a four wicket win over Manawatu.
William Doherty took 5-27 as his side bowled Manawatu out for 66, a target they reached in 17 overs.
There were a number of good bowling performances on show, as Manawatu spinner Mitchell Chrystal snatched a hat trick against Wanganui in their Saturday afternoon T20 game.
After a getting a batsman caught and then clean bowling the next, Chrystal induced a drive and a great diving catch was taken in the field to secure the treble.
Thanks to a very good partnership by the final pair of Dinwiddie and Blair Pudney, Wanganui still put up a 133-9 target and won the match by four runs.
In another surprise, Wanganui's Ben Huijs got a five wicket bag in his three overs for the Invitational side in their Saturday morning match against Manawatu.
Not a regular club player, Huijs said his last games at this level of competition was taking part in the Under 12s tournament of the Festival.
"I'm playing backyard and stuff, so had a little experience."
