The Strikers will play the Sydney Sixers in the second semifinal on Friday.
The Sydney Thunder plays the Perth Scorchers in the opening playoff match tomorrow.
Bates has been instrumental in the Strikers' run to the playoffs. The 30-year-old all-rounder is the team's leading scorer with 420 runs at an average of 32.30 and a strike rate of 109.94.
She blasted a 65-ball century earlier in the tournament and remains a potent threat.
She led the Sparks to glory in the New Zealand domestic twenty20 competition last summer with a defining innings of 74 from 52 balls.
Fellow New Zealander and Strikers team-mate Sophie Devine is the second-highest leading scorer for the side with 348 runs at 26.76. She has also been very handy at the bowling crease with 15 wickets at 18.46.
The pair have formed a productive opening partnership for the Strikers but the team will be worried heading into the semifinal. It suffered back-to-back defeats to the Sixers on the weekend.
Fellow Otago player Katey Martin was called into the Melbourne Stars for its final two round-robin games. Both games were against the Hobart Hurricanes.
The series was split one game apiece. Martin scored 15 and two not out during her brief cameo in the tournament.
The Women's Big Bash League final is scheduled for Sunday so Bates will be free to play in the Sparks' next match on February 8 against Auckland in Lincoln.
