New Zealand have made it four wins out of four in their home Test summer, and become No. 1 in the world in the format for the first time, while also extending their unbeaten streak at home to 17. Kane Williamson feels this consistency is down to "the drastic changes in terms of the culture" in the team put in place during Brendon McCullum's stint as captain, which has given them the license to play fearless cricket.

"My observation of teams is that over a period of time, you have changes in personnel and obviously under Brendon the drastic changes in terms of the culture started things off to a large extent," he said after New Zealand swept the two-Test series against Pakistan with an innings-and-176-run win at Hagley Oval in Christchurch on Wednesday. "From our perspective, it's just been trying to build, grow and adjust when needed as time goes by, and that's a continuation, and something that we'll try to focus on and continue to improve on.

"I don't know how the rankings work exactly, but I know they sort of span over a period of time, which, I suppose, means that there's been a lot of hard work over a lot of matches and trainings and all these sorts of things to to reach that. So a very special moment from the guys. It was hard to talk about until perhaps the summer was over, so it's nice to be able to sit back now and enjoy the moment."

"Their efforts that went into just trying to move the team forward, and perhaps get the side across the line, that's really special and something that we do focus on as a team and try to build on as a unit moving forward as well"

Kane Williamson on Kyle Jamieson and Daryl Mitchell

New Zealand have now won six Tests at home in a row, against India, West Indies and Pakistan, their best streak ever, and it's kept alive their hopes of making it to the World Test Championship final at Lord's in June.

Williamson was named the Player of the Match in Christchurch for his 238 in New Zealand's only innings, but Kyle Jamieson, playing only his sixth Test, was as crucial to the outcome with his match haul of 11 wickets. Only Richard Hadlee (thrice) and Daniel Vettori (twice) have had better match returns than Jamieson's 11 for 117 for New Zealand, while only three bowlers with at least 20 wickets have had better averages than Jamieson's 13.27 after six Tests.

"Some younger guys have come in, the likes of Daryl Mitchell [who scored his maiden Test century in Christchurch] and Kyle Jamison, you know, especially in this game where there were some outstanding performances, contributions… But more the attitude that they brought in terms of their performance is most satisfying," Williamson said. "Their efforts that went into just trying to move the team forward, and perhaps get the side across the line, that's really special and something that we do focus on as a team and try to build on as a unit moving forward as well.

"Kyle is extremely good at bat and ball, a very, very special talent. I think if he continues to - and I'm sure he will, he's got a great head on his shoulders - bring that great attitude that he has… things have come very thick and fast for Kyle, which is a really enjoyable part of the game, but also something that he's learning a bit about as well and learning about himself.

"He's got a real strong desire to improve and pick the brains of some of these other senior guys that have been around for a long time, so he's a humble guy and a player that just wants to continue to get better."

As for Pakistan, they did show some fight in the second innings of the first Test, almost forcing a draw courtesy the 165-run partnership for the fifth wicket between Fawad Alam and Mohammad Rizwan. But they have been outplayed outside of that in all departments.

"The game is truly a game of small margins - we're very pleased with the efforts that went into these last two games, but we we know the quality side that the Pakistanis have," Williamson said. "There were definitely moments in both games that either went our way, or perhaps moments that we seized that went a long way to changing the result or putting the result in our favor.

"I guess, on the scorecard, this game appeared to be one-sided, but you knew it wasn't as the quality that they have in their attack, that things can happen really quickly with the new ball."