With captain Kieran Noema-Barnett marshalling the troops, the Stags had the Otago Volts reeling at stumps on 232-9 with Ian Butler bringing up a half ton.
But the day belonged to the hosts in the four-day Plunket Shield match at Nelson Park, Napier.
Nethula had brought up maiden century after resuming on 87 runs overnight while Milne agonisingly fell three runs shy of emulating his teammate on the heels of No 3 Carl Cachopa's fightback with 123 on Monday following the collapse of the other top-order batsmen.
"You always look at yourself as a lower-order player so you tend to nudge it around a little bit but you also try to get runs for the other man as well," Milne said, politely asking to sit down at the pavilion not long after heaping more misery on the visitors with a five-wicket bag.
The 20-year-old right-arm seamer batted with leg spinner Nethula for a while until the No 8 started getting away so he tried to keep in touch.
"The runs kept coming so I just kept batting."
The Manawatu rep impresses the CD squad are oozing with players adept with the bat and ball.
He hadn't had much time to dwell on it but the heart was a little heavy on missing out on scoring a century.
"Yeah, falling three short was pretty disappointing, I guess, but there's not much I can do about it."
So did he choose to take out that frustration on the Volts batsmen?
"Yes, I guess I did a little bit. I sort of went out to do the best I could for the team," he said, claiming 5-44 from 12 overs, including a maiden.
Milne had the Otago top order rattled as he had the visitors reeling at 22-3 before completing his maiden first-class five-wicket haul by knocking over Otago skipper Derek de Boorder and Jimmy Neesham later in the day.
He had honed his skills while with the Black Caps' in the abbreviated form on the tour of Sri Lanka.
"Being in different conditions you learn a little bit more about yourself and what you need to do to change your game in those conditions."
He said playing against the calibre of Sri Lankan players often did the New Zealanders a world of good.
"You can build your confidence and bowl against anyone."
Milne harbours the ambition of representing his country in all three formats of the game and his first-class efforts won't go unnoticed with New Zealand director of cricket John Buchanan here for a few days to watch the top-of-the-table clash.
"With the tests it's about playing a lot of first-class matches and getting a lot of overs under my belt and staying injury free."
His form might be a signal in the changing of guards with New Zealand on schedule to tour South Africa next month and a long-in-the-tooth Chris Martin appearing to fall out of favour with the national selectors. He hasn't been given a start in tests on the current trip to Sri Lanka.
No 11 Blair Soper has yet to score when he resumes with Butler today although there's risk of showers tomorrow.
The visitors are 244 runs behind on the first innings, and face a momentous task in the next two days to avoid a substantial defeat.
English import and Somerset county allrounder Peter Trego, who began his campaign with the Stags in the losing HRV Cup Twenty/20 match last Friday night in Hamilton, picked up 3-52.
Nethula said it was a nice feeling to chalk up his maiden ton.
He posted 108 from 210 balls, including 13 boundaries, as the India-born player beat his previous-best knock in first-class cricket of 58, while Milne was the last man dismissed as he departed for 97 - in what would have been his maiden first-class hundred.
"It was more than a ton," the Heretaunga Building Society Cornwall player said
With six wickets down he backed the batsman at the crease but when he departed Nethula and Milne commendably picked up the highway project of building the record partnership.
The former Black Cap legspinner rightly pointed out the era of tail-enders collecting record number of ducks is over.
"You saw Bruce Martin get a hundred the other day and Michael Bates got 50-odd here.
"Butler today batted 50-odd at No 9 so these days everyone bats deep so it's our job to make sure we're not left behind and we're contributing with the bat."
Nethula shared Milne's agony of missing out on a maiden century.
"I think Dougie [Bracewell] got 97 here last year but Adam made up for those three runs for the first six balls he had bowled by taking three wickets.
"You know he [Milne] is one ahead of Dougie now with a 97 and a fiver."
CD coach Alan Hunt felt it was fruitful day.
"It was a very good day to post a good total and then have them nine down at the end of the day."
"I couldn't ask for too much more. If had bowled them out, sure, it would have been nice but there's still two days to go so a lead of 240 gives a great position to work towards tomorrow to try to win this game."
Hunt said the Kieran Noema-Barnett-captained Stags took pride in their work.
"Tarun hasn't fulfilled his potential with the bat until now so I'm really pleased for him," he said, adding it would boost his confidence immensely.
"Milney has built on his confidence in Gisborne [in the win over ND] where he played very well," Hunt said, pleased with the international's calmness and surety.
"You wouldn't believe he is No 9, would you?"
A grinning Hunt ruled out any talk of promoting Milne up the order on the grounds of Nethula's knock.
"Tarun's got 108 and he only got 97 so we can't do that."
It brought a sparkle in Hunt's eye, reflecting on how Milne terrorised the Otago batsmen.
"He was quick and certainly a couple of them were a little bit late on it but he did bowl some beautiful deliveries to put the top order under pressure.
"He'll probably admit he didn't quite get it right for a little period there but when he came back I thought he was good for those five wickets."
With a 244 lead and Otago having a first-innings wicket in hand, Hunt didn't fancy accommodating thoughts about batting again.
"If I was a gambling man I think I'd be bowling tomorrow morning and through for the rest of the day."
While it was a hot day again yesterday he was confident fitness trainer Anthony Sharp's ice baths would keep them hungry.
"Hopefully we'll be fresh in the morning to get that early wicket and the carry on.
"The leads too big and there's too much time left to bat first."
To pad up again would give Otago a sniff to win the game.
"At this point we've outplayed them so they don't deserve that opportunity."
At the Eden Park Outer Oval in Auckland, Colin Munro stroked his third first-class century to ensure the home team held the smallest of first-innings leads over Wellington by the close of play on day two.
Munro finished the day unbeaten on 122 - his knock included 14 fours and five sixes - as the Auckland Aces closed play on 381-5 in response to Wellington's first-up effort of 380.
Craig Cachopa was the less aggressive of the Auckland pair to finish the day; unbeaten on 74 from 145 balls at stumps.
Earlier in the day, Auckland were in a bit of strife at 174-5 as the top order all made starts but failed to kick on past 50. Tim McIntosh, Lou Vincent, Reece Young and Colin de Grandhomme all made scores between 31 and 46.
The Wellington Fireirds will need to take early wickets today to avoid facing a large first-innings deficit.
