Pace bowler Holly Ferling will miss the games as she manages an elbow injury, with 15-year-old Murgon pace bowler Renee Irvine coming into the squad.
Replacement players must play in the starting XI or be selected as twelfth man for their first upcoming matches.
Under the WBBL playing conditions for this season Ferling will be able to resume her place in the squad once she becomes available again.
Irvine, an Australian U-18 squad member who turns 16 this month, made her debut for the Konica Minolta Queensland Fire during the WNCL in November.
West Indian import Deandra Dottin continues to recover from a fractured cheekbone suffered in an on-field collision with teammate Laura Harris.
Harris has been cleared to play against the Thunder.
The Heat will apply to the WBBL Technical Committee for a replacement international player in due course.
WBBL Heat coach Andy Richards said Ferling hoped to return in the near future. “She’s working hard and we will continue to keep her in our plans,” he said.
“Renee had a good taste of what is required at this level when she had a few games for the Fire during the WNCL so she will continue to build her experience,’’ he said.
All WBBL non-broadcast games will be live streamed by Cricket Australia for free to watch on cricket.com.au, the Cricket Australia Live App, and - in a first for Australian women’s sport - also via the WBBL Facebook page.
WBBL Brisbane Heat v Sydney Thunder
Monday & Tuesday - 1pm. Blacktown Sports Centre
Delissa Kimmince (c), Beth Mooney, Kirby Short, Jessica Jonassen, Laura Harris, Smriti Mandhana, Jemma Barsby, Sammy-Jo Johnson, Kara Sutherland, Renee Irvine, Haidee Birkett, Georgia Prestwidge, Tess Cooper