It's the sporting event that has gripped the nation, and come Sunday, the chewed finger nails of cricket fans from Cape Reinga to Bluff will come under scrutiny once more as the Black Caps chase World Cup glory.

And as the side prepares for the biggest cricket match in its history, SunLive spoke to those who have helped shape the skyrocketing careers of Bay of Plenty products Trent Boult and Kane Williamson.

Kane Williamson (left) and Trent Boult will fly the flag for the Bay of Plenty in Sunday's Cricket World Cup final agaist Australia.

The Bay pair have been vital cogs in the Black Caps' machine during the tournament, and face the biggest test of all against Australia at the Melbourne Cricket Ground showcase on Sunday.

Boult has set the bowling statistics alight, including his best figures of 5/27 when he ripped the heart out of Australia at Eden Park during the group stages.

Tuesday's 2/53 in the semi-final win over South Africa means he is now New Zealand's highest-ever World Cup wicket taker (21), overtaking Geoff Allott's 20 in the 1999 tournament.

Boult's teammate Williamson might not be reaching the dizzying heights of teammates Brendon McCullum and Martin Guptill, but his top score of 57 against Sri Lanka in the opening match, along with consistent knocks since, has seen him amass 222 runs so far.

Tuesday's nail-biting victory marked the start of a frantic 48-hour period for the Williamson clan, who are attempting to secure tickets and flights across the ditch to support their son in the final.

Boult's parents Ian and Wendy are also making the trip across the Tasman.

'Trying to get our kids to Australia has been hard,” says Kane's father, Brett Williamson. 'We have been trying to get his brother and three sisters to Australia and also accommodation - the same problems everyone else is facing.

'It's a once in a lifetime opportunity. It's pretty exciting, but it's a pretty crazy time.”

Reflecting on the children growing up, Brett doesn't believe Kane was any different to his siblings and their chosen sports.

He says while Kane was passionate about cricket, but as a parent he never thought too far ahead. Williamson was pretty special in the schoolyards of Pillans Point Primary School, Otumoetai Intermediate and Tauranga Boys' College.

'Destiny seems to make its own way,” admits Brett.

”I just know that looking on the screen after Tuesday's win, and judging by the reaction, it obviously means a lot.”

One of the Williamson's former mentors, Ben Williams, says both the batsman and Boult were always destined for big things.

Williams, who established the Ben Williams Cricket Academy in 2006, says the pair's natural skill levels from young age was hard to miss, with both performing strongly at a Bay of Plenty age group level.

When it comes to the left arm of Boult, it's was his unwavering self-belief and 'superb” wrist position that got Williams excited.

'When he was 13 or 14,” says Ben, 'he was just a medium pacer, but you could see with the alignment of his wrist and his action he had something pretty unique and the ability to swing the ball.

'Every kid is encouraged to believe in themselves, but believing it and actually living it is a different story.

'For Trent, it's not an arrogance, it's just a state of belief that was present from a young age. That's something that should inspire youngsters.”

When it comes to Kane, Ben says he was lucky enough to coach the batting superstar, but insists he was nothing more than a trusty arm for Williamson to hone his skills.

'I've just been a donkey really, giving him a billion throw downs,” says Ben. 'He's been able to tap into my resource called my right shoulder.

What sticks out for Williams is the 24-year-old's composure and ability to absorb pressure - even in the fiery cauldron of international cricket.

'I remember a game when he was 13,” he says. 'He had scored three 100s in four matches, so we thought we would drop him down to 10 in the batting order. He still ended up scoring a 100 and keeping his composure with the number 11 who wasn't the sharpest batsmen.”

Otumoetai College cricket coach Nick Page also pays tribute to Boult, who was an integral part of the school's first XI between 2003 and 2006.

Page co-coached Boult alongside Gareth Osmond in the first XI, while the school competed in the Bay of Plenty men's senior reserve grade before he was released to play senior men's cricket with Cadets.

One match that sticks in Page's mind is a 2005/06 match with the Greerton Senior Reserve men's side, where Boult headlined an impressive spell from the Otumoetai College bowlers.

Posting a score in excess of 250, Boult and the rest of the school's bowlers combined to skittle their opposition - for just 12 runs.

'The thing that comes to mind is he was incredibly focussed and determined, even as a youngster,” says Nick. 'And had a mental toughness and maturity well beyond his years.

'As a bowler, it was amazing how effortless it all seemed and how rhythmical his action was.”

'We have followed his career with quite a lot of interest.”

Upon leaving school in 2007, Page coordinated a Year 13 leaver's item about what might happen to students in the future and, ironically, Boult's predicted career lay in cricket.

'I doctored a photo of him with his mug shot on a picture of Richard Hadlee doing one of his famous appeals,” adds Nick, 'with the implication that Trent might one day be one of our leading wicket takers.”

In 2015, the lofty heights that Boult's fledgling career has reached suggest Page's prediction was bang on the money.