In reply to the Scorchers' 5-146, the Strikers were restricted to 2-16 in the six-over powerplay before finishing at 6-134 in Saturday's clash.

Kapp, who had been sick all week, scored an unbeaten 31 off 23 balls in the 33-degree heat to help lift the Scorchers to a solid total, but her greatest contribution was with the ball.

The 31-year-old's first two overs in the powerplay cost just two runs in a display that put the pressure on the Strikers straight away.

Kapp finished with 1-25 from her four overs, with those figures including a maiden against her wife, Strikers opener Dane van Niekerk (six off 13 balls).

The Scorchers had played in two finals previously - both of which ended in losses to a Sydney Sixers outfit that featured Kapp.

But this time the Scorchers had Kapp on their team, and it proved to be their lucky charm.

After the match, Kapp revealed she had been mostly confined to her hotel room all week after being struck down by illness.

"On Monday, when we travelled back from Adelaide I already wasn't feeling too great," Kapp said.

"I woke up the next morning and I was so sick. For the last three days I was so sick and I didn't move out of my room.

"I knew today was going to be really tough, especially with the heat as well.

"After the batting, I felt like I was going to pass out, I didn't feel well at all, but at the end of the day it was worth it.

"You don't play in finals a lot. I got pulled out of the World Cup semi-final earlier this year (with a mystery illness) and it's something that still hurts.

"Tonight, I wasn't going to do that again and lucky my team came out on top."

A crowd of 15,511 watched the decider, the biggest attendance for a stand-alone WBBL match.

Star Scorchers openers Sophie Devine (35 off 33 balls) and Beth Mooney (19 off 25 balls) struggled to get going after the home side were sent in, with the duo never really finding their groove despite sharing a 52-run opening stand.

Kapp made a nervy start to her innings and failed to score off her first four balls, but the South African soon found her groove.

Her stunning early work with the ball left the Strikers shell-shocked, and the visitors were in disarray when star opener Katie Mack (six off 13 balls) was dismissed by Devine in the fifth over.

Strikers captain McGrath (36 off 29 balls) and Laura Wolvaardt (25 off 28) combined for a 65-run stand to give their side a slight chance, but in the end, the task was too great.

"They bowled really well up front in the powerplay and probably just left us a little bit too much to do in the back end," McGrath said.

"We put up a good fight but it just wasn't enough in the end."

Australian Associated Press