"We did have to work for it, they had to lift themselves as they were hugely disappointed after Hawke's Bay's game," said manager Kellie Watkin.
After coming fourth in 2013 and heading to Nelson with the hope of bettering that effort, their early elimination from the top grade saw the girls sit down together on Wednesday night and make the vow they would finish ninth, the highest placing now available to them.
They had to come from 1-0 down early against Southern to tie the match at halftime and then go on with it as Watkin made a hat trick of goals.
Two came from penalty corner strikes while the third was a field goal.
"They sort of stuck to the plan, it all just happened for them," said Kellie Watkin.
Wanganui's final game with Taranaki starts at 9.40am.