Heat collapse as top-two finish hopes fade

Brisbane Heat's hopes of hosting a WBBL final are slipping away after a dramatic collapse resulted an upset nine-run defeat to Sydney Thunder in Mackay.

In the day's second WBBL|07 boilover, the Heat were cruising at 0-99 in the 12th over in pursuit of the Thunder's 5-162, but a combination of calamitous run outs and ill-judged shots saw them lose 9-51.

It followed Melbourne Renegades' shock loss to Hobart Hurricanes earlier in the day, leaving Perth Scorchers in the box seat to claim top spot and a home final if they can finish the season with back-to-back wins.

The Heat need the Scorchers to lose their remaining games, to the Stars and Sixers, and defeat the Renegades on Saturday night, in order to finish in second spot and host the mid-week Eliminator and Challenger finals.

Georgia Redmayne (54 off 52 balls) and Grace Harris (50 off 34) had the Heat cruising in their run chase, with first Harris and then Redmayne bringing up half-centuries.

But when Harris holed out to Sam Bates immediately after reaching the milestone and Laura Kimmince suffered the same fate looking to attack the left-arm spinner a ball later, the tide started to turn.

Ellie Johnston was promoted up the order but could not replicate the heroics of cousin Ruth for the Hurricanes earlier in the day, run out for one as the Heat lost 3-4.

A second mix-up saw Georgia Voll (2) depart cheaply, and then Redmayne was removed in the 17th over the wheels fell off.

Bates (2-25), Deepti Sharma (2-21) and Hannah Darlington (2-23) caused havoc with the ball, as the Heat were kept to 9-153.

Earlier, Thunder opener Sammy-Jo Johnson cracked 52 off 36 balls to power her side to a formidable total.