The toss was lost, drizzle was falling, it was time to go out and face the new ball. The Prime Minister was in attendance, there was pomp and ceremony. It was the opening match of a World Cup. All that would have been enough to break the resolve of a lesser man.

Instead, there was a lesson in how to grasp a moment: Brendon McCullum style. He was on strike after four balls, preparing to face Nuwan Kulasekara with rain still hanging in the air. The bat hammered the popping crease then was raised like a battle-axe, his knees flexed and his eyes widened. A split second later, the ball was drilled over cover.

From some players it could be questioned whether it was a release of nervous tension; that the batsman wasn't really in control. But McCullum's control was absolute, as it has been as a batsman and captain for the last 18 months. The next ball he faced, his first from Lasith Malinga, was punched sweetly off the back foot through the covers.

McCullum's powers are unlikely to stretch to parting the clouds, but as he started to unleash, the thick morning cloud cover, which had threatened to keep everyone in suspense a little longer, began to lift. Christchurch's biggest sporting occasion since an earthquake in 2011 devastated the city took shape.

While nothing could be taken for granted, inside the first 10 overs of New Zealand's innings there was a sense that nothing was going to deny them their day. It rekindled memories of how Virender Sehwag launched the previous World Cup with a string of boundaries against Bangladesh in Dhaka.

McCullum's innings was just what New Zealand needed to prove both to themselves, and those watching (17,228 was the final count inside the ground), that they had not been overcome by the occasion. This team are certainly not short on confidence, but it was still an uplifting experience to see the captain take the opening exchanges of the tournament by the scruff of the neck.

It was not as vast as some opening-day World Cup innings - 65 from 49 balls - and across the Tasman the first hundred went to Aaron Finch, but the value of an innings is not always in runs alone.

"He has a massive calming influence on the dressing room," Corey Anderson said. "We all know Baz; that when it's a big event he turns it on. He spoke to us the day before the game but said he wasn't going to give us a motivational speech. There was nothing we needed to hear."

Setting the agenda is becoming McCullum's trademark and when he took 22 off Malinga's fourth over there was the odd, hushed mention of his 195 here in the Boxing Day Test. That day he took Sri Lanka's young spinner, Tharindu Kaushal, to the cleaners but on this occasion the wily Rangana Herath enticed him down the pitch again (although it does not take much to lure an attacking stroke) and he could not clear long-off. There was an audible sigh from the crowd, but there had been plenty of entertainment for them.

What followed fed off McCullum's lead, ensuring that the performance was as complete as he could have wished for, given the occasion. His electrifying start provided breathing space for his team when Sri Lanka belatedly found some consistency to their bowling through Herath and Suranga Lakmal. There was another fifty for Kane Williamson, albeit not his most fluent as he was dropped twice, then the innings was rounded off by Anderson's highly mature 75 off 46 balls.

This New Zealand side are so well-drilled in their one-day game plan that minor hiccups do not panic them, but if McCullum's chest-thumping display stole the moment early on then the role of Anderson, after he walked in following the loss of two wickets in two balls, was also highly significant as it reinforced how responsibility is passed down the order.

Then, in the field, New Zealand were pressed for a time as Sri Lanka made a decent fist of the early part of the chase. But, again, the confidence bred came to the fore. McCullum stuck with Trent Boult when others may have removed him from the attack and he was rewarded when Boult fired one under Lahiru Thirimanne's bat while Adam Milne, who was clocked at 149kph second ball, responded to an opening four-over spell that cost 30 with six fiery overs later on.

And, when McCullum - in a pre-planned move - brought Daniel Vettori back to bowl at Mahela Jayawardene the result was his wicket, fifth ball. Just the sort of moment that goes the way of a winning team.

In 1992, delirious New Zealand fans invaded Eden Park when Andrew Jones caught Bruce Reid off Chris Harris to complete a victory. Such post-match displays of euphoria are now firmly in the past, courtesy of health and safety, although two brave men did decide to run on to the playing area and probably won't be returning to Hagley Oval anytime soon.

The rest of the crowd - those who did not want hefty fines and to be manhandled by half a dozen security guards - instead savoured their team's effort from the stands. You are up and running New Zealand. Enjoy the ride.

Andrew McGlashan is a senior assistant editor at ESPNcricinfo