New Zealand's James Neesham, BJ Watling and Brendon McCullum after clinching the Test series against India, 18 February. Reuters

"I have never experienced anything like that before," said Brendon McCullum right after becoming the first New Zealand batsman to score a triple century in Test cricket.

McCullum set a new milestone in New Zealand cricket scoring a splendid 302 in the second Test against India on Tuesday. Only two former New Zealanders have come close to the 300 mark before. Martin Crowe made 299, and was the previous record holder, with Stephen Flemming, another former captain, scoring 274.

McCullum said he didn't realise just how big a triple ton was till he got close to the mark. "That's something I'll hold onto for the rest of my life," he said. "All the tough times and tough periods you go through when you're out of form and you're just trying to keep the faith in what you're trying to achieve.

"And just knowing there are plenty of good people out there who are backing you. In that moment, I realised how much satisfaction you can bring people from the way you achieve stuff and that certainly gave me a lot of good feelings.

"Without being disrespectful, I probably didn't know the magnitude of it until the last 24 hours.

"I grew up and watched the New Zealand cricket team for years on end. I watched Martin Crowe score his 299 and thought it would have been an amazing feat if he scored 300 but probably didn't quite understand how much it meant to the whole country who support this team and the media and support that has started to gain momentum last night and this morning with everyone willing a New Zealander to break that 300 barrier.

"I saw him [Crowe] this morning on the Breakfast show and he was discussing how significant it would be. I guess that was one of the things that made me realise how big a moment it would be.

"I also spoke to Stephen Fleming last night. He said the same thing and those are the two guys who sat at 1 and 2 on the table. I feel a little bit embarrassed because I'm nowhere near the calibre of players they were but I think in terms of New Zealand cricket and moving forward for this team, we have finally broken that 300 barrier and hopefully some of these guys will continue to break that barrier."

McCullum was roared on by the supporters with every passing delivery as he inched closer to the massive triple hundred.

"I wasn't too bad until I saw the size of the crowd then every ball that I defended, left or got a single they would start cheering and it made me a little bit more nervous," he said after the knock that turned the game in New Zealand's favour.

"That's probably when I understood the magnitude of the task at hand and the immense joy it gives fans of this cricket team to see guys succeed and see records broken. It was a moment when 300 came up and the applause was ongoing for quite a while is really when it hit home to me that it was quite a significant achievement for a New Zealander and I'll certainly remember them for the rest of my life."

The Black Caps set India an insurmountable target of 435 to win in only 67 overs. McCullum was proud of his team's effort especially that of Watlings' and Neeshams' who scored 124 and 137 respectively. He also said he couldn't risk India coming back into the match by declaring earlier.

"We were 1-0 up in the series and [with] two and a half days to go, we were staring down the barrel of an early finish on day three," he added. "Thankfully I had partners at the other end who played brilliant innings. I thought BJ and Neesh, their innings were outstanding.

"We were obviously scrapping to save the Test and therefore win the series and we managed to get some partnerships under pressure and then kept batting and batting and batting.

"We didn't want to pass up all that good work we'd done to try and give India a sniff back into the series. I always try and win but at some point you've got to acknowledge the game was out of your reach and then you fought your way back into it.

"Hence we made sure we got a score where we knew we were not going to lose, then we could be as aggressive as we wanted, and hopefully if we got some early wickets then some pressure might set in. But they're class players and they stood up.

"So yeah it was pretty satisfying to get us out of trouble and claim the series win."