Young spinner Bryant Galpin, who would never had bowled more than a 12-over spell in his club career, had to trundle on for nearly 32 overs, taking 3-153 after he initially had the most success on day one for Wanganui - dismissing the first century-maker in Jacob Smith (107) from a good running catch by Hamish Harding.
Matt Boswell grabbed a nice slips catch off Galpin to get the other opener, Matt Edmondson for 55, but would grass another attempt late in the day as Wanganui's woes in the field were not just from the batsmen - Rayner getting hit in the face, while Dominic Lock injured his thumb and Nick Harding's leg issues continued.
Beforehand Wanganui had some fight with the bat, reaching 199 as Callum Coker raised his maiden half century - returning to the crease on 38 after he had to come off with a strained arm earlier, which was the price paid for facing over 100 deliveries in the intense heat when the body is not conditioned to two-day cricket.
Boswell (37) and Chris Sharrock (33) also tried their hardest in the last representative match of the year, but the confident bowlers, young Liam Dudding (4-44) and Angus Schaw (2-21) eventually caught up with them, while the tail folded after little contribution as Dudding got amongst them.
While the total represented a better effort than recent games, one could not help think that given Wanganui's struggles with the willow this season, the baking pitch and fast outfield must likely be a batsman's paradise - which Hawke's Bay soon proved.
Edmondson and Smith launched for an opening stand of 123 in 27 overs, with Smith carrying on to near the very end of the day, as Hawke's Bay passed Wanganui's total with around three overs left to set off cheers from the players' tent.
By gaining first-innings points, Hawke's Bay knew they had won the Furlong Cup competition, with Wanganui having to play on for survival.
Wanganui manager Justin Lock had heard the visitors had set themselves a goal of 550 to make sure of the Cup's possession on all fronts, but they would eclipse that through their inspired tailenders, and probably batted an hour or two longer than needed yesterday if an outright win was the goal.
Starting on 227-3, Rupert Young, who had supported Smith on the Saturday, upped his game to reach 104 before being trapped in front by Rayner, who would get a couple of middle-order wickets including wicketkeeper Scott Schaw (46), the last recognised batsman.
However, from 385-8 and the possibility of salvaging something from the match, Wanganui were blitzed by Pretorius, who raced to 60 off 40-odd balls, and then Thompson got into the act, notching his century off just 95 balls after he took to Galpin.
Hawke's Bay did send Wanganui out initially to see if it was worth trying for the innings victory, given they were 413 runs ahead.
While John McIlraith fell early, Boswell reaching 32 from 24 balls was enough to convince the visitors that calling the game off and getting a cold drink from the Cup was a better way to spend the rest of the afternoon.
On paper, a first-innings points loss with a draw for Wanganui reads far better than some other results this year.
But the massive 612 total, with most of the strike bowlers ineffective and the part-timers copping a lot of stick, is a sad indictment on the state of the local game at this level.
In the search for positives, Boswell making a couple of scores atop the order is encouraging, if a little late, and Galpin deserves credit for an ironman bowler's effort in the hot conditions.