The Buccs were the expected victors heading into the contest, with home-court advantage and a six-game win streak behind them.
But sixth-placed Wanneroo got an early jump on Geraldton to secure a 34-22 lead in the first period. It proved to be a game-winning deficit, with the Buccs unable to respond despite their star forward Robert Kampman hitting 36 points.
Wanneroo drained 13 three-pointers at a potent 54.2 per cent return, led by Trian Iliadis (29 points) and Seb Salinas (23 points) who hit five each.
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READ NOWRob Huntington took nine boards to lead the Wolves’ rebound count, while also racking up 24 points. Reece Maxwell continued his solid form with 13 points.
The victory firmed up Wanneroo’s hold on sixth place heading into a tricky end to the regular season. The Wolves face a double-header this weekend, which pits them against second-placed Perry Lakes Hawks on Friday, before meeting the Stirling Senators (12th) on Saturday.