Tied behind them in second are Steelform Wanganui and North Otago, with Wanganui holding the better points differential.
But North Otago served notice they could be getting back to the form that made their union two-time Meads Cup winners after a thrilling 34-33 win over Mid Canterbury in Ashburton.
Both team's scored five tries in the Hanan Shield clash, with fullback Dan Fransen scoring two for Mid Canterbury, while team standouts Timoci Nabakeke and Seta Koroitamana also crossed.
But leading 33-27 with six minutes left, Mid Canterbury were put under the pump and North Otago finally forced their way over to close the gap to score two minutes into injury time.
Josh Buckham, who would contribute 14 points, was able to land a stunning conversion from wide out into a south-east wind to steal the match.
Both winger Simon Lilicama and prop Ralph Darling scored tries in the second week in a row for North Otago.
It was a weekend where only one of the six games was won by the home team, as South Canterbury rebounded from their loss in Whanganui to pick up an ultimately comfortable 40-11 win over Poverty Bay in Timaru, after they went on a blitz with four tries in the last 13 minutes.
The home side took a while to click into gear, with Poverty Bay still in with a chance at 19-11 after one intercept try by Matt Raleigh try.
But then South Canterbury cut loose through their backline, with centre Shayne Anderson, who missed the Wanganui match, smashing through the midfield for two tries.
Hard working captain Nick Strachan got the final five pointer, while debuting Canterbury import Daniel Dorgan added five conversions.
Thames Valley rebounded from their loss in the dying minutes to West Coast by travelling to Masterton's artificial turf and picking up a 44-32 win over Wairarapa Bush in a high scoring affair.
Thames Valley scored six tries with Sam McCahon getting a double, while Kieran Lee like McCahon also scored for the second week in a row.
Reece Broughton added 16 points with the boot.
Wairarapa Bush received the second of two automatic seven point penalty tries for the weekend, which helped them to a bonus point.
Horowhenua Kapiti likewise rebounded from their loss to North Otago by heading to Ruatoria for a confidence boosting 46-8 win, with former Steelform Wanganui players were all over the sheet.
Centre Timoci 'Jim' Seruwalu, the Ngamatapouri club player and Meads Cup winner with Wanganui, has gone on loan to Horowhenua Kapiti this season and scored two tries, as did standout winger Willie Paia'aua, who was injured before last year's final.
Reserve halfback Kane Tamou, yet another former Meads Cup winner with Wanganui who made the switch last year, also got a try, while Trent Reti added 16 points with the boot as their team moved up into the important fourth spot.
Results, Week 2
Wanganui 33 (Dane Whale 2, Craig Clare, Kamipeli Latu, Angus Middleton tries; Clare 4 con) bt West Coast 21 (Tom Reekie, Brad Tauwhare tries, penalty try; Reekie con, Oliver Dimmick con).
Thames Valley 44 (Sam McCahon 2, Jesse Dodunski, Christian Kelleher, Kieran Lee, Ben Bonnar tries; Reece Broughton 4 pen, 2 con) bt Wairarapa Bush 32 (Nick Olson, Epeli Rayaqayaqa, James Goodger tries, penalty try; Glen Walters 2 pen, 2 con)
King Country 30 (Dean Church 3, Chulailynn Mabbett-Sowerby tries; Euan Reihana 2 pen, 2 con) bt Buller 28 (James Lash, Maifea Feso, Michael Wells tries; Wells 3 pen, 2 con)
South Canterbury 40 (Shayne Anderson 2, Setefano Sauqaqa, Kalavini Leatigaga, Zac Saunders, Nick Strachan tries; Daniel Dorgan 5 con) bt Poverty Bay 11 (Matt Raleigh try; Ethine Reeves 2 pen).
North Otago 34 (Josh Buckham, Ralph Darling, Inoke Naufahu, Junior Fakatoufifita, Simon Lilicama tries; Buckham pen, 3 con) bt Mid Canterbury 33 (Dan Fransen 2, Tom Heywood, Timoci Nabakeke, Seta Koroitamana tries; Andrew Letham 4 con).
Horowhenua Kapiti 46 (Timoci Seruwalu 2, Willie Paia'aua 2, Kane Tamou, Stewart MacGregor tries; Trent Reti 2 pen, 5 con) bt East Coast 8 (Ngarangi Haerewa try; Haerewa pen).
