It was an innings set up by a 254-run partnership between twin centurions Jeet Raval and Tom Latham on Friday, but Saturday was dominated by Kane Williamson, who reached his second double century, crafting an exquisite unbeaten 200 which left McMillan singing his praises.
"He was sublime today – whenever the Bangladeshi bowlers missed, he hurt them, he was very efficient when they offered scoring opportunities and created those partnerships that we talk a lot about.
"It's not easy, and it takes a lot of hard work behind the scenes that allows him to play like that. He's very hard to bowl at as he bats 360 degrees – all around the wicket. Bowlers only have to err a fraction with Kane, and he hurts them, and we saw that today – a terrific knock all around."
While Williamson could have gone on to threaten his high score of 242 – and even Brendon McCullum's 302 if the Black Caps were feeling really ambitious - McMillan explained the reasoning to pull the pin with plenty of time left up their sleeve.
"The milestones weren't an issue at all. We wanted to bat for a period where we could see the wear and tear in the surface – starting to see those cracks open up and develop a little bit. [Williamson] obviously reached that milestone and thought 'Now's the time' – and we wanted the bowlers to have a decent crack, not just a short hour at the end of the day.
"To pick up those four wickets was very satisfying at the end of the day."