Merewether scored three tries in the final eight minutes to pip Lake Macquarie 34-33 at Walters Park to claim outright fifth place and poll position in the race to the finals.
Wanderers bounced back from their loss to Southern Beaches to beat The Waratahs 40-30 after leading 23-6 at the break.
Southern Beaches claimed a second straight major scalp, coming from 14-7 down to overpower Hamilton 32-14 at Passmore Oval.
In a bigger upset, University produced their best performance of the season to storm past Maitland 28-13 at Uni. No.1 Oval.
Nelson Bay ended a five game losing streak with a 60-14 triumph over Singleton at Rugby Park.
Premiers South Newcastle ran roughshod over Cessnock 52-12 in a catch-up game at Townson Oval to all but a seal a berth in the top five.
Black Diamond AFL
Nelson Bay overcame a determined Killarney Vale 16.15-111 to 7.7-49 at Adelaide Street to secure fourth spot and a place in the finals.
The Marlin’s win ended any hope of Warners Bay featuring in the post season. The Bulldogs went down anyway to an under-manned Newcastle City 9.13-67 to 7.6-48 at Feighan Park.
Cardiff earned a psychological advantage over Terrigal Avoca before their major semi-final clash with a 14.5-89 to 10.11-71 win at Hillsborough Oval.
Northern NSW NPL
Lambton Jaffas came from 2-0 down to win 4-2 over the Newcastle Hets youth team at Edden Oval and wrap up third place.
In the late game, Broadmeadow Magic play Hamilton Olympic at Darling Street.
Herald Women’s Premier League
Merewether are the first team through to the 2017 Herald Women's Premier League Grand final after downing Adamstown 4-0 at Myamblah Oval on Saturday in the second leg of their home-and-away semi-final.
United finished 6-1 up across the two legs after winning 2-1 in the first leg at Adamstown Oval on August 6.
Merewether took a 1-0 lead on Saturday around the 15th minute when set-piece specialist Jamee Ellis scored from a corner kick.
Newcastle Open Netball Championships
BNC kept their title hopes alive with a 45-36 triumph over a depleted Forsythes at National Park. BNC will meet the loser of next week’s major semi-final between minor premiers Wests Leagues and Souths Lions.