With the scores tied at 34-34 at the start of the third quarter, a close finish seemed likely, but the Swifts put a stranglehold on the game with a flurry of scoring in the final 15 minutes.
The win leaves the Swifts unbeaten, having conquered the Southern Steel in Invercargill eight days earlier.
The Magic could point to the loss of goal shoot Harten towards the end of the first half as the cause - but the home side showed at times that, even without her, they were capable of holding their own.
Captain Leana de Bruin praised the young players coming in to fill the injury-enforced gaps.
"It's always disappointing (to lose) but we came up against a quality side with a lot of experience and we've got young girls, some of whom have only taken to the court for the second time (tonight)," she said. "Injury-wise, we lost another one of our top players and I think to lose by five is a great effort from those young guns."
Sam Sinclair started at centre with Jamie-Lee Price at wing defence, coach Julie Fitzgerald switching them at the half, when she also swapped Harten's replacement, goal shoot Malia Paseka, with goal attack Ellen Halpenny.
"We are just settling those combinations," said de Bruin.
"Jamie is pretty good at centre and swapping her and Sam just brings something different for the opposition to think about."
With the game won and lost in the final quarter, de Bruin believes the experience will be telling.
"We missed a few little crucial shots at times, but that comes with the experience of that pressure - those (Swifts') defenders are so experienced and obviously we didn't turn as much ball as we'd like to in the last few minutes, which is something we'll definitely need to work on."
Earlier in the game, it was the Magic defenders who were applying the blowtorch to the visitors.
"They (the Swifts) were definitely uncomfortable in the first half, which is obviously a credit to the defence - that's our job and we try to do that as well."
The Magic play a second game at ASB Arena on Sunday when the Melbourne Vixens are the visitors. The game starts at 7.10pm.
The game will be co-captain de Bruin's 100th ANZ Championship game.