Nelson Bays and Mid Canterbury will be fighting for the last spot in the second-division playoffs in their final round-robin matches.
Hawke's Bay (29 points), Counties-Manukau (21) and Manawatu (20), despite a heavy loss to Hawke's Bay in Napier, have qualified for the semifinals.
Thames Valley, last in the division, will drop to the third division next season.
Fourth-placed Nelson, with 16 points, meet Manawatu in Palmerston North on Saturday and fifth-placed Mid Canterbury (13) face Counties in Pukekohe.
Counties replaced Manawatu in second spot after they beat Marlborough 34-15 in Blenheim, and Manawatu went down to Hawke's Bay 10-32 in Napier.
Mid Canterbury enhanced their chances by beating East Coast 38-19.
It was only in the second half that top qualifiers Hawke's Bay ran away with the match, after trailing 5-7 at halftime.
Against the smaller Manawatu opponents, the Hawke's Bay forwards showed a lack of respect and were troubled. Manawatu were unlucky not to have a bigger lead at the interval.
But with their eventual victory Hawke's Bay secured a home semifinal and retained the Colin Meads Challenge Cup and the KR Tremain Memorial Trophy, which is contested annually between the two provinces.
Nelson Bays scored 35 second-half points to swamp Thames Valley 49-18 at Nelson's Trafalgar Park.
A big Thames Valley pack dictated much of the play for a start. They opened up an early 8-0 lead after a Teri Rahui penalty, followed by a try by prop Carl Tremayne.
Although never totally error-free, Nelson Bays eventually distanced themselves in the second half as further tries by Dunn, centre Aaron Kimura (two), first five-eighth Mark Milne - from a 75m run - and flanker Karl Leary shut Thames Valley out of the contest.
Counties, after two successive losses, beat Marlborough 34-15 at Lansdowne Park. Marlborough spent long periods deep inside opposition territory but failed to nail several try-scoring opportunities.
The turning point came seconds from halftime. Marlborough's forwards had dominated through a powerful scrum and effective, driving mauls from lineouts and were leading 15-12 through tries by front-rowers Tau Fainga'anuku and Mark Stewart.
However, when fullback Sam Gibbons muffed a clearance inside his 22, Counties seized on the chance and scored through Josh Heke.
Counties-Manukau played more expansively and centre Casey Laulala showed fine form.
In a forward pack that struggled at times, lock Kristian Ormsby stood out, along with Heke and lock Ramon Lindsay.
Fullback Gus Leger pulled off two try-saving tackles and winger Niva Ta'auso scored two good tries.
Marlborough's best were flanker Craig Simeon and prop Tau Fainga'anuku.
A more disciplined second half enabled Mid Canterbury to repel East Coast 38-19.
North Otago became the first third-division team to qualify for the playoffs with their 49-29 win over Poverty Bay 49-29 at Oamaru, maintaining their unbeaten season.
Horowhenua-Kapiti also earned a bonus point in their 29-20 win over West Coast at Greymouth, helping them to level with second-placed King Country on 25 points, although King Country still have an edge on points differential.
King Country coach Peter Fatialofa was relieved with his team's 31-18 win over Buller in Taupo.
He said his team played "dumb rugby" at times.
The home side scored three tries through No 8 Paulo Maevaega, first five-eighth Dideon Malifa and wing Ronnie Patea.
- NZPA
NPC schedule/scoreboard
Last playoff spot strongly contested
AdvertisementAdvertise with NZME.