Round 15 of the Bayleys Southern Districts' Premier competition provided two massive upsets which could have huge implications come playoff time.
Mid Northern's 12-game winning streak came to an abrupt halt in thrilling fashion.
While they looked to lock up their 13th win on the trot, Mid Western spoiled the party with a hard-nosed effort to snatch the 18-17 victory.
Mid Western's win was made even more significant when Kamo upset third-placed Waipu.
Waipu were desperate for points as they have the toughest run home of any team, but couldn't get the job done against a spirited Kamo side, who won 18-17.
Otamatea, another side caught in the logjam between third and ninth place, were beaten 41-29 by Old Boy's Marist.
With the win, OBM move to the top of the table.
Western Sharks catapulted themselves into the top four, beating fourth-placed Wellsford 31-5 at Farmlands Park.
Hora Hora, like Kamo, have given themselves an outside chance of making the top four with a 49-17 win over Hikurangi.
The week's results have shaken up the finals race with just three rounds to go.
Meanwhile, the top two sides in the Bay of Islands Seniors increased the distance between themselves and the pack.
With two top-four clashes, both Ohaeawai and United Kawakawa looked to catch up to the leaders.
However, Moerewa and Kerikeri proved why they are the teams to beat.
Moerewa dismantled Ohaeawai 44-5, while Kerikeri defeated United Kawakawa 28-10.
In the other results, Okaihau beat Otiria 22-17 and Kaeo took the home win over Kaikohe 24-14.
Awanui maintained their lead in the Mangonui Senior competition with a 51-12 victory over Panguru.
Kaitaia picked up a 41-10 win over Aupouri, while Te Rarawa snuck home with a tight 20-15 defeat of South Hokianga.