Brisbane Heat 197 for 5 (G Harris 54, Knott 32*, King 3-30) beat Perth Scorchers 130 for 8 (Sciver-Brunt 36, Voll 4-19, Jonassen 2-25) by 67 runs
Grace Harris smashed a half-century to deflate Perth Scorchers before offspinner Georgia Voll claimed four wickets as Brisbane Heat stormed into the WBBL final after a commanding performance at the WACA.
Having flown cross-country before playing on consecutive days, an indefatigable Heat relished a fast surface to post the highest score in a WBBL final. They then bowled and fielded with discipline in a superb defence to stun a crowd of 2226 fans.
Heat will play Adelaide Strikers in Saturday's final at Adelaide Oval. They've had to do it the long way after a convincing 44-run victory over Sydney Thunder in the elimination final at the WACA just a day earlier.
"It's always a great match-up when we play them. It's going to be a great final," Voll said with Heat and Strikers having split their two games this season. "It's going to be an awesome atmosphere and hopefully we can knock them over one more time."
It was a disappointing end for Scorchers, who sat on top of the ladder before losing their last three matches of the regular season. Their slump continued against Heat with a ragged bowling and fielding effort proving costly.
"Definitely a tough one, pretty stunned for words. But the dust will settle and we can celebrate what's been a really great season," Scorchers legspinner Alana King said.
Harris vindicated captain Jess Jonassen's decision to bat first in sunny conditions with a whirlwind in the powerplay. She had emerged from a form slump with 45 off 22 balls against Thunder and continued the momentum with a second ball boundary after charging offspinner Amy Edgar.
Harris was equally destructive against pace and thumped quick Chloe Ainsworth through the covers in the next over.
Harris scored 33 of Heat's 41 runs in the first four overs with struggling opener Georgia Redmayne intent on turning over the strike. The end of the powerplay did little to curb Harris, who continued her aerial assault including a six over long-on that thundered into the mammoth sightscreen under the ground's famous light towers.
She fittingly reached her half-century with a boundary off seamer Piepa Cleary, who in frustration bowled a bouncer that flew way over Harris for a no ball.
Scorchers resorted to allrounder Nat Sciver-Brunt, who was playing her last game of the season regardless of the result. She stood up with the key wicket of Harris by trapping her lbw in a decision that was upheld after an umpire's call on review.
Without Harris, Heat were pinned down in the middle overs with Sciver-Brunt bowling an accurate full length, while King was a constant wicket-taking threat.
Heat were in danger of again falling away in the latter overs much like against Thunder, but Laura Harris stepped up with consecutive sixes off seamer Sophie Devine in the 17th over.
Charli Knott, on her 21st birthday, then took over with 32 off 14 balls as Heat had one foot in the final.
Devine did not take up her favoured position at the top alongside Beth Mooney. Instead, Lauren Winfield-Hill held onto her opener's role and smashed 15 runs quickly before falling to quick Nicola Hancock.
It wasn't long before Devine came to the crease at No.4 alongside Mooney as the pair briefly provided a flicker of hope for Scorchers. But they fell in quick succession with the burden on Sciver-Brunt, who attempted a rally against the odds.
But when she fell lbw to Jonassen on 36, it was only a matter of time before Heat wrapped up a memorable trip to Perth as they kept alive their bid for a third WBBL title.
