A new technique netted massive returns for hammer thrower Matt Bloxham, as he smashed his personal best and then a New Zealand record.

He's now being talked about in similar terms to shot put sensation Jacko Gill, 17, of Takapuna.

Bloxham, 15, an Orewa College student from Waitoki, had a personal best of 60.04 metres going into the Sovereign Spring Series at the Millenium Institute in Mairangi Bay.

But he was trialling a new four-turn technique and it helped him to beat his PB by more than 11 metres, the old M16 record by nearly 8m and the M17 record by more than 4m. Bloxham started with a fouled throw, but the 5kg hammer landed well beyond the 60m flag.

The second throw was safe and landed even further at 67.56m - a PB by more than 7.5m.

It was an Auckland and New Zealand record for M16 and M17.

And the throw also qualified him for the IAAF World Youth Championships to be held in Donetsk, Ukraine, next year.

There was more to come.

Bloxham's third round throw measured 67.67m, to increase the records.

In the fourth round, judges reportedly did a double take when measuring the distance at 71.33m.

It was the first time for a New Zealander of that age to break 70m.

With two throws left, Bloxham put the fifth out of bounds, but that was estimated at around 70m, while his last effort was a relative anti-climax at 65.18m.

Bloxham now needs to raise funds to get to the Ukraine - and on Tuesday he was also selected for the New Zealand team to go to the Australian Youth Olympics in Sydney in January.

- © Fairfax NZ News