Five players named are set to make their Super Rugby debuts in Viliami Taulani, Zane Kapeli, Tom Florence, Rivez Reihana and Gideon Wrampling, while former Blues prop Ezekiel Lindenmuth is making his first appearance for the Chiefs.
McMillan concedes the team chosen would look a lot different had they not already locked up a spot in the competition final.
"If the Blues had got a bonus point last week it certainly would've forced our hand a little bit more to keep rolling the guys out. So we've been fortunate."
McMillan says the need for rest for his usual first-teamers is as much a catalyst for the mass changes.
"We've had a number of dings, particularly in our forwards – that's been over the last month or so that we've been rolling out the same guys week after week barring the odd person.
"There are just some tired bodies, and I probably doubt our ability to run the same people out for two weeks in a row and get a positive result. That's not to say that we won't get a result this week by rolling out the team that we've done."
Those usual incumbents in the starting side have navigated through taxing matches recently, with the Chiefs coming from behind in their last five games to claim wins that have played a vital part in them securing a finals spot.
McMillan says for the inexperienced players included this weekend, it offers them a great opportunity to "demonstrate they're good enough to play in the following week and put their hand up for regular selection through [Super Rugby] transtasman".
"I've made it really clear that there's probably seven spots up for grabs in the matchday 23 against the Crusaders, so everybody that plays has a massive amount to play for."
A familiar face who will come off the bench is Chiefs legend Liam Messam, who was brought in earlier in the week as injury cover for loose forwards Kaylum Boshier and Mitch Karpik.
McMillan says the former All Black has settled in well.
"He's been good. He's been training with us on and off for the last five or six weeks off his own bat, just to keep in shape and wait for an opportunity. No issues around his ability to hit the ground running."
For the Blues, pride is all that's on the line as they look to finish what's been a disastrous 2021 Super Rugby Aotearoa campaign on a high.
They will need to do so with a few youngsters thrown in the mix as well, with 20-year-old Zarn Sullivan set to make his debut at fullback. Bryce Heem gets his second start of the year on the right wing, while Finlay Christie returns to start at halfback.
In the forwards, Tom Robinson returns to the blindside, while the injured Dalton Papalii is replaced by Adrian Choat at No 7.
