A smart half century from Beth Mooney and a five-wicket haul for spinner Alana King have propelled Perth Scorchers to a 28-run WBBL win over Brisbane Heat at the WACA.

Mooney (77 off 52) rescued her side after a mid innings collapse left them precariously placed at 6-106 in the 17th over.

They recovered to post 8-142 after being sent in.

Laura Harris (40 off 21) threatened to snatch victory from the Scorchers, bludgeoning 16 in the space of four balls from spinner Amy Edgar in the 17th over, to leave the visitors needing 31 off the last three.

But the end came quickly after King had Harris caught at long off.

It was the first of three wicket in five balls, with just one run added, as Heat were dismissed for 114 with two overs left.

King (5-16 off 4) took all of the last four wickets as she returned her best WBBL figures.

The Scorchers improved to 2-1 and the Heat dropped to 2-2.

Perth were quite well placed at 2-81 in the 12th over, but lost 4-15 before Mooney boosted her side with some effective late hitting.

She looked all at sea in the first over, playing and missing three times against impressive Indian quick Shikha Pandey (1-17 off 4).

Mooney put on 40 In an opening stand with Sophie Devine (25 off 22).

Devine struck some handsome offside boundaries before being yorked by Nadine de Clerk (2-31 off 4).

Nicola Hancock (3-23 off 4) induced two batters into mistiming a short ball and giving an easy catch.

Mooney struck just three fours in her first 40 runs of steady accumulation, but went through the gears and into overdrive in the last three overs.

The prolific left-hander struck five of her nine fours in that period as the Heat piled up 34 runs off the last three, before she was bowled behind her legs by Hancock off the last ball of the innings.

Mooney appeared to injure a finger and handed the gloves over to England wicketkeeper Amy Jones halfway through the Heat innings.

Brisbane lost both openers in the Power Play and slumped to 3-38 in the sixth over, despite a typically belligerent start from opener Grace Harris (14 off 9).

They looked out of contention at 7-87 after 15 overs, but Laura Harris made them sweat before King's final over proved decisive.