Tonight's game is a repeat of last year's preliminary final which the Mystics won 43-42.
Last weekend Magic beat Adelaide Thunderbirds by one goal to make the preliminary final, showing they have what it takes to win in a pressure-cooker situation.
Naoupu is expecting a physical game against Mystics and says both teams will be "giving it all they've got".
An instinctive rather than strategic player, with movement and ball skills that come naturally, Naoupu admits fitness is something she's had to work on in recent years.
"I've really taken it seriously this year, stuck to my routine ... I guess I've just grown up really, am taking responsibility for what I'm meant to be doing."
Naoupu says she's "not sure" what happened at the beginning of the season when Magic lost four games in a row before constructing a comeback that saw them win 10 consecutive games.
The key to the turnaround, she says, is that the players have higher expectations of one another, which they are open and upfront about.
"We all need to be on the same wavelength to be successful... you don't want to let anyone down. If one of us falls short the whole team does."
Her weekly routine is something Naoupu has been working on and it has shown in the progress she's made, better fitness seeing her in the game for the full 60 minutes and picking up the slack when playing partner Irene van Dyk is under added pressure.
"I think I'm more consistent now and I've been able to fine-tune and execute better, perfect things."
Her partnership with van Dyk has certainly improved, the two in perfect unison for much of this season.
"Last year was a real learning curve for both of us, not having played together before, but having the world No1 at the back is a massive confidence booster for me," Naoupu says.
"I've also been working hard to get my shooting stats and speed up ... I'm pretty happy with how I've been playing but I haven't hit my straps yet. I think there's still more to come."
Magic coach Noeline Taurua hopes last week's win over Thunderbirds will stand her side in good stead.
Magic were under the pump for long periods in that match, unable to break through until the final minutes when perseverance, discipline and tenacity created an opportunity that led to the win.
"All these games have been beneficial to us because it's helped us handle different situations ... it's also us being in the right mindset," Taurua says.
She expects Mystics to look to their bench to change the on-court chemistry if and when needed tonight. For their part, Magic will make some minor tweaks to readjust to the New Zealand style of play but have mainly stuck with what has served them well so far this season and are going in with the same aim as all their previous games - to be better than the previous week.
Magic v Mystics, The Trusts Stadium, Auckland, 7.40pm.