The Mystics' win means the Tactix will now have to travel for next week's elimination final against the Steel.
The Steel will now meet the Tactix in a fortnight for a spot in the final against the Mystics.
The Northern side maintain their place atop the competition table.
The world champions will face their archrivals on each side of the Tasman.
The Auckland-based side have lost their last three games.
Maia Wilson took to social media earlier this week to talk about her ongoing personal issues.
The 23-year-old has taken to social media to share her story.
The Steel are now one point behind second-placed Northern Stars on the competition ladder.
The result sealed a three-game clean sweep over their crosstown rivals.
The Southerners are up to third on the ladder with four games to play.
Victory over Northern Stars sees them leapfrog their rivals with four games to play.
The 17-point victory is the biggest in their ANZ Premiership history.
The win sets up a mouthwatering top of the table derby against the Stars on Sunday.
The Steel will be sweating on the fitness of star import Georgia Fisher, who was forced from the court with a head injury.
The shooter landed 57 goals to steer her side to victory in Hamilton.
The three-goal win sees the Stars' lead in the standings trimmed to one point.
Last year's ANZ Premiership finalists are scrambling to stay in contention for this year's playoffs.
It lifts the Auckland squad three points clear at the top of the ANZ Premiership ladder.
The reigning champions sealed back to back wins for the first time in 2021.