Reigning WBBL champions Perth will miss the finals after losing to the Melbourne Renegades by six wickets in a rain-affected contest.
Showers made play difficult in the regional Victorian town of Moe, with Sunday's crunch match limited to eight overs.
The Scorchers had to beat the Renegades and rely on other results going their way to be any chance of making the top-four.
New Zealand star Sophie Devine hit an unbeaten 24 to help the Scorchers to 2-46 after they were sent in to bat by Renegades skipper Hayley Matthews.
The Renegades' chase was in tatters at 4-15 after Perth's opening bowler Lilly Mills skittled the top order with figures of 3-9.
But a brilliant innings from Erica Kershaw turned the Renegades' fortunes around as she smashed unbeaten 34 to make more than half of Melbourne franchise's total.
It will be just the second time in eight seasons of WBBL the Scorchers will not feature in the finals after clinching their maiden title last year.
Meanwhile, the Sydney Sixers will enter Saturday's home final full of confidence after notching an emphatic eight-wicket win against Hobart.
The Sixers racked up their 11th win from 14 starts this campaign as they restricted the Hurricanes to 156 batting first.
Superstar Ellyse Perry is back to her all-round winning best, taking 2-16 and top-scoring with an unbeaten 56 as the Sixers cruised to victory with seven balls to spare.
Fellow Australian player Ashleigh Gardner continued her sparking form with an unbeaten 45.
The last three spots on the ladder could still change heading into the final game of the regular season between Sydney Thunder and Adelaide.
Brisbane had a chance to secure second spot on the ladder and a home final ahead of their clash with the Melbourne Stars.
But the match was abandoned as storms returned to hit Moe.
The Stars had got their run chase off to a flying start in a match already reduced due to rain.
The Heat made 5-104 from 10 overs batting first thanks to a blazing 52 from opener Danielle Wyatt.
But the Stars batters looked to be in even better touch as they raced to 1-49 from four overs before storms forced players off the field.
The Strikers will secure second spot if they defeat the lowly Thunder in what will be captain Rachael Haynes' last game before retirement.
