The Heat won the toss and elected to bat in the first fixture of the day, as both teams looked to ramp up their preparations ahead of WBBL Opening Weekend.
The visitors started quickly, with opener Laura Harris smashing 33 off just 11 balls, before Grace Harris continued the onslaught notching 55 off 37 balls.
Sarah Aley (2/38), Carly Leeson (1/15), Stella Campbell (1/21) and Lauren Smith (1/23) were the pick of the Sixers bowlers as the Heat finished on 7/165 from their 20 overs.
In response, the Sixers were led by newly-signed young gun Tahlia Wilson, who scored an impressive 59 off 56 balls. Wilson was well supported by fellow rising-star Hayley Silver-Holmes (24 off 26 balls) as the pair kept the Sixers in the hunt with a 60-run partnership.
However, the required run-rate proved to be too much of a mountain to climb as the Sixers eventually fell 45 runs short of their target, finishing on 8/120 from their 20 overs.
Wilson picked up where she left off in the second fixture of the day. With the Sixers batting first, she smashed eight boundaries on her way to 54 off 42 balls, setting the tone for the innings.
Sixers train-on product Maddy Darke was equally impressive, scoring 65 off 54 balls to help the home side to a competitive total of 4/151.
An impressive 41-ball 70 from Heat power-hitter Sammy-Jo Johnson took the match into the final over, but a pair of wickets to Sixers skipper Sarah Aley (3-23) ensured the home side held on for a 5-run win.
Erin Burns (3/19) and Campbell (2-22) were also impressive with the ball in the Sixers' narrow victory.