Is this the biggest game of the World Cup so far? On the basis of the first few overs, what sort of score are we looking at today? Who's your money on to win?

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It is a packed crowd at Eden Park and the home fans are in good voice with oohs and aahs as David Warner loses his footing, just about keeping out Trent Boult's final ball of the over. It is a good over, with only three off it to slow Australia's charge.

Andrew Samson
BBC Test Match Special statistician

"The last time a team scored 15 off the first over of an ODI was Canada against Afghanistan at Voorburg on 1 July 2010. Canada scored 17 in the first over of that match."

Pete Naylor:, external This game has started like me on a cricket game - proper stroke, slog, slog, wicket. Let the carnage continue!

Ex-Australia spinner Shane Warne: Buckle up your seat belts & enjoy the show today, should be a ripper.

Jeremy Coney
Ex-New Zealand captain on BBC Test Match Special

"The ball is moving - New Zealand will feel that's their last chance. Yes, you're going to get hit down the ground a bit, but you've got that chance. McCullum has got three slips and he's backing his bowlers."

So in four matches, Southee already has 12 wickets. Shane Watson failed against England, but scores his first runs of this year's World Cup, flicking a full toss away just behind square on the leg side for four. Australia going at 12 an over so far. We told you this was going to be good.

Jeremy Coney
Ex-New Zealand captain on BBC Test Match Special

"It just moved away slightly. It was pitched well up, inviting the drive. Perhaps Finch was looking to the on side as he aimed to repeat that stroke."

Aaron Finch hits Southee for a powerful six off the first ball of the third over, over long on, but what a response from the fast bowler. His delivery is too fast, too accurate and too good and sends the off stump cartwheeling out of the ground. Finch out for 14, next man in Shane Watson.

Scorecard

Image source, Getty Images

The last time Australia were meant to be playing New Zealand, David Warner had been in the headlines after punching England batsman Joe Root in the face in a Birmingham bar. As it turned out, that game in 2013 was then abandoned because of the weather.

But Warner hopes to make the headlines for the right reasons today. He gets a huge slice of luck as, off Trent Boult, Warner takes a wild swing, and has no idea where it has gone, but is quite pleased to see it vanish, almost into the top tier. Nine off the over.

Jim Maxwell
BBC Test Match Special

"This looks like a kid's game, end to end. It's tiny."

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Jeremy Coney
Ex-New Zealand captain on BBC Test Match Special

"A great start for Australia - that could be a huge confidence builder for the Australia openers."

Here we go. Tim Southee storms into Aaron Finch, who swings wildly at it, but it is a huge wide. Some early nerves from the paceman, who destroyed England with 7-33 last Friday.

Finch then flicks one off the pads for three.

As starts go, this over quite simply is a disaster for Southee. His third ball is a wide, before another Finch boundary. What a start for the visitors. They score 15 off the over. Four byes came off the last one. He couldn't have bowled like this against England could he?

As Andrew mentions, the straight boundaries at Eden Park are only 55 metres. The ICC regulation is a minimum of 64m, but as it was an existing venue prior to those minimums being brought in, then it is exempt from the regulations.

So, with some of the best one-day batsmen in the world on view today, we are expecting the rope to be cleared a lot today.

Andrew Samson
BBC Test Match Special statistician

"The square was turned at Eden Park in 2010, making the straight boundaries short.

"In the 24 ODIs at the ground from 1 Jan 2000 until the square was turned, there were an average of 7.9 sixes per game. In the six ODIs there since then there have been 12.2 sixes per game."

A great moment for all the snappers at the game as Australia Prime Minister Tony Abbott poses next to his New Zealand counterpart John Key, before some passionate singing of the national anthems. You get the impression this match means a lot to both sides. No one wants to lose to your nearest rivals.

Image source, AFP

Vic Marks
Ex-England spinner on BBC Test Match Special

"Australia have been the big brother in these cricketing struggles. But if ever the Kiwis can play with freedom, it's this match.

"New Zealand are playing some exceptional, dynamic cricket, but perhaps there's a little barrier there that they need to get through."

Vic Marks
Ex-England spinner on BBC Test Match Special

"It will be a grand occasion. It's quite a tribal affair and it's almost a game within a game - they're playing for a trophy.

"It's a huge game. And for the victors, it improves their chance of playing at home in the semi-finals."