Big defensive plays provided the inspiration for the win, with Harrison's hoist the standout.
The veteran defender drew gasps from the crowd before halftime when she elevated her wiry frame above the rim to pluck a shot from Tegan Caldwell out of the air.
Then in the final quarter, as the Vixens were making their now customary late charge, she was twice hoisted by Jessica Moulds to intercept goal-bound attempts by replacement shooter Karyn Howarth.
While the shock tactics caught both the opposition and commentators off guard, Mystics coach Debbie Fuller said they had worked on the defensive lift for the past month.
"I sat [the defenders] down in training one day and said 'I want you to try this, and if we're going to do it, we're going to do it properly'," said Fuller. "They've spent a lot of extra time working on it, and we've really studied the science of it."
In Harrison the Mystics had the perfect prototype for the defensive experiment - she has a long, lean physique, a superb standing jump and exceptional timing, honed from her three years on the professional beach volleyball circuit.
But the strategy has proved controversial with social networking sites abuzz last night with claims of cheating.
Some may view goal tending as not in the spirit of the game, but so long as the defensive player does not interfere with the goal or net, there is nothing in the rule book to suggest it is illegal.
Vixens coach Julie Hoornweg said she had absolutely no problems with Mystics tactics, admitting it was something her side had tried in training.
"We have practised it, but we don't have the same elevation as a Harrison. I think a lot of teams have thought about it and tried it, but you need to have a very tall player with great elevation to pull it off."
Harrison's impact yesterday may prompt their rivals to look at the ploy more seriously in training. But Fuller is not worried.
"Teams could potentially do it against us, but our shooters have been training against it for the past month, so they've developed strategies to prevent it from happening."
While Harrison's unorthodox defensive work was a feature of the Mystics' strongest performance of their campaign, shooters Cathrine Latu and Maria Tutaia combined to ensure the visitors had a big enough buffer to protect down the stretch.
Tutaia finished with shooting statistics of 26/34, contributing more goals than Latu (23/24).
