Cricket World Cup: How McCullum and Williamson are carrying the Black Caps batting

Kane Williamson is averaging 74.50 at the Cricket World Cup. Photo / Brett Phibbs

After the euphoria, the cold-eyed analysis.

New Zealand will almost certainly top Pool A after their nerve-shredding win against Australia, but it's what they do in the next couple of weeks, against minnows Afghanistan and slightly bigger fish Bangladesh, that will determine their readiness for potentially three knockout games against tough opposition.

Truth is, New Zealand's batting is in bit of a mess. Take Brendon McCullum and Kane Williamson out of the equation and you're left with a line-up whose confidence seems to be eroding by the game.

Between them they have scored 356 of New Zealand's 754 runs to date. That's 47.21 per cent of their team's runs.

Mike Hesson and his staff must know that is not sustainable, particularly given McCullum's modus operandi. Even given his supernatural hand-speed and locked-in eye, the chances of him going through the tournament without failing is unlikely.

Here's the rest of New Zealand's top eight, with batting position in brackets*:

There is some grim reading there on a number of fronts. Between them, six of New Zealand's top eight have mustered 355, one run less than Williamson and McCullum. Extras (42), have contributed more to New Zealand's aggregate than Taylor and Vettori combined, though the latter has had only two bats.

There has been only one 50+ score among them, that being Anderson's powerful 75 against Sri Lanka on the first day of the tournament.

Some of this is beyond Hesson's control. Three times in succession the opposition have batted first and made paltry totals, meaning that even if New Zealand's order were all in the form of their lives, there wasn't a lot of runs to share around.

This goes for time in the middle, too. Ronchi, an important free-scoring cog at No 7, has faced the equivalent of six overs; Vettori, one spot lower in the order, just seven balls. Taylor has faced 8.1 overs and Elliott 11 overs worth of deliveries. It is difficult to get a true gauge of form with such a small sample size.

Of the rest, only Anderson and Guptill will feel like they have had any significant time in the middle, and of those two only the former, batting at No 6, will feel like he has made a solid contribution.

Winning, however, tends to cloud these sorts of issues, but the brainstrust will be acutely aware that they need their batsmen, particularly the vitally important Taylor, to be feeling better about their games heading into the quarter-finals. This is going to make selection for the game against Afghanistan far more important than it would normally appear.

All the talk is that the dirt-trackers - Tom Latham, Kyle Mills, Mitchell McClenaghan and Nathan McCullum - will get a run, and certainly on the bowling side that would make some sense. But can they actually afford to play Latham?

The gaps between games now are so big, that it would be a risk to rest your in-form players, because there's a danger you play them out of form due to inactivity - the game against Bangladesh, where they will surely revert to their best XI, is not until March 13, and then there is another eight-day gap until the Caketin quarter-final.

If you played Latham at No 5 instead of Elliott, who had been in great pre-World Cup form but good a good 'un first up against Mitchell Starc, you're potentially robbing the Wellingtonian of his best chance to get into the tournament. Guptill might have been vulnerable pre-tournament, but he showed enough patches of form to convince selectors he was the best foil for McCullum. Again, it would be unwise to rob him of the chance of a confidence boost and time in the middle against the minnows.

It might be that McCullum's bruised forearm provides them with the perfect excuse to get Latham into the team, but as mentioned before, that comes with its own risks around that nebulous subject - momentum.

All those permutations aside, one thing should be certain. With the bowlers in great form and the batsmen struggling, this might be the most crucial toss of the tournament to date: New Zealand need to call correctly and take first use of what is normally a benign McLean Park surface.

* We'll ignore the tail because if you're relying on runs from Nos 9-11 in 50-over cricket, your problems are insurmountable.