THE Giants AFLW team were singing in the rain after they created a little piece of history with first ever win on Friday night.
GWS led at every change but were pushed to the limit, holding on in a 3.2 (20) to 1.9 (15) thriller.
The Demons dominated possession in the nailbiting final term but could manage just five behinds. They will rue their terrible conversion rate, finishing with just one goal for the match.
Giants marquee player Emma Swanson missed a shot for goal after the siren but it was academic as her teammates started celebrating before the kick.
"They were exceptional," Giants coach Tim Schmidt said.
"Our first half in particular was super. We matched them if not beat them in the contested area. They couldn't capitalise on their forward entries and we held tough and kept our cool."
It was a critical loss for the third-placed Melbourne, who still had hopes of a spot in the grand final.
With the top two teams set to play off in the season-ender, an Adelaide-Brisbane match-up now looks likely.
The Demons need the Crows to lose its top of the ladder clash against the Lions on Saturday night and then must beat them in Adelaide next Saturday night if they are any hope of making the decider.
"We're bitterly disappointed," Melbourne coach Michael Stinear said.
"It was a game we desperately wanted to win. We were slow to start and credit GWS they were first to the ball. When we got our effort up we just couldn't convert."
Swanson was again outstanding as was Jess Dal Pos who finished with 19 disposals and seven tackles.
The slippery conditions suited Dal Pos as she picked up possessions at will working hard around the ground in and under the packs.
Jacinda Barclay made a welcome return from suspension to provide at target up forward.
Her first goal was all class when she dummied a handball and finished from 30m to open the Giants account.
Her effect was blunted after the long break by Dees defender Katherine Smith.
The win temporarily moves GWS from eighth to fifth on the ladder.
Karen Paxman continued her outstanding form for the visitors picking up a game high 25 disposals.
Daisy Pearce was also impressive with 21 disposals as was Lily Mithen (13) and Elise O'Dea (15).
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