He also hinted spinner Keshav Maharaj would come in for Wayne Parnell.
Black Caps captain Kane Williamson said the make-up of his side depended on the look of groundsman Mike Davies' maiden test wicket.
"We want to get his [Davies] thoughts on some subtle differences that we might have experienced previously on this surface," Williamson said.
"By all accounts it will be similar to what we're used to. The green grass might offer a little bit to the seamers initially.
"The wicket in the past has been liable to change quite quickly."
New Zealand have not lost at the venue since its 2008 debut. They have won three and drawn four, including a stalemate against South Africa in 2012.
Local knowledge suggested the ball nibbles about for bowlers in the 120-130km/h bracket.
The two Plunket Shield matches in November produced draws where seam and spin shared the wickets.
In the second match, between Otago and Wellington, Patel took six wickets for 55 before rain intervened. He also had a sustained bat at practice.
"He's been bowling well and is an aggressive spinning option," Williamson said.
"The Dunedin surface has taken a bit of turn and slows up, so he's an option we're considering."
The skipper also weighed up the Neesham versus de Grandhomme conundrum.
"Colin can exploit seam movement in surfaces and Jimmy can bowl with good pace and make things happen with it."
After losing five straight tosses in the one-day internationals, Williamson was coy on what he might do if the coin landed in his favour.
"I don't want to get ahead of myself with silly ideas like that," he quipped.
"We'll have another look at the surface tomorrow before we make any outrageous comments about what we might do."
If history is a gauge, Williamson will field tomorrow. That's what the toss winner has chosen in the previous 22 New Zealand-hosted tests.
Watch: Faf du Plessis ahead of the first test
Speaking of decisions, Du Plessis was affirmative on Morkel's recall.
"Every time he's bowled in the nets [over the last six months] he's been at his best when I've faced him.
"Morne is successful against lefties and that's one of the main reasons he got the nod ahead of Duanne [with New Zealand expected to have four in their top seven].
"Bounce is a huge factor and the angle of the ball as it comes out of his hand - it goes into right-handers or away from left-handers. He's terrible to face in the nets as a right-hander because you always feel like it's going to hit you in the ribs."
Morkel has not played a test since January 2016 but a record of 17 wickets at 20.94 in five tests against New Zealand further justifies his selection.
