"I'm really proud of BJ," McCullum said. "Everyone knows what a scrapper he is and how hard he works. He has that real resilient streak, especially coming off a duck as well."
Watling said it was a rewarding grind.
"We just took each ball at a time, each over at a time, each hour at a time. To lose one wicket [in the day] was a pleasing effort. The third day was about getting through and trying to fight back. Today was pretty much the same. That first hour was crucial."
Watling said he tried not to get caught up in the hype as records fell.
"I wasn't really thinking about those, to be fair. The announcer said a few things but nah, you're just trying to bat each ball.
"We had a couple of chats [between overs]. We talked about staying in the moment and taking the next over. We tried to get to that [third] new ball and keep building the lead."
Watling sensed Indian heads dropping as New Zealand made 319 for one in the day.
"I guess after more than 150 overs in the field that tends to happen. We've probably got an hour tomorrow to see how we sit. It's still a good batting track but I think if the conditions are right our bowlers could swing it and put them under pressure."