A dodgy hamstring means Papamoa's Kodi Harman won't be around to defend his national beach sprint and flags titles this week, though he's got the recently-acquired title of New Zealand's fastest man to ease that disappointment.

The 20-year-old flyer won his first senior 100m title at the New Zealand track and field championships in Wellington on Friday, clocking 10.47 seconds ahead of Auckland's James Mortimer (10.62) and Alex Jordan (Wellington), who was third with 10.65.

Papamoa's Kodi Harman, right, on his way to victory in last year's national beach sprint championships. Photo: Jamie Troughton/Dscribe Media Services.

His jubilation was tempered, however, when he pulled out of the 200m heats due to injury.

'I came around the bend and my hammy tightened,” says Kodi. 'I didn't actually pull it but it tightened pretty badly so I didn't even walk through the line.

'It still feels pretty tight so I'll just go and get some treatment and hopefully be back at least jogging next week.

'It's been an up and down season - I've been fighting so many injuries since I got back from surf worlds and it's been frustrating, so I was pretty surprised to come away with the 100m win.”

He'll miss the New Zealand surf lifesaving championships, which start in Gisborne on Thursday, having become only the sixth man to win the beach flags/sprint double last year at Ohope.

Surf lifesaving helped launch his athletics career and he came away with a beach sprint bronze at last year's world championships in France.

He aims to be fit again for the Australian track championships at the end of this month, with the Australian surf lifesaving championships and the world university games also looming.

Friday's win meant he now has a full collection of national junior, youth and senior 100m titles, although the latest would've been a lot sweeter if great mate and training partner Joseph Millar had also been able to line up.

Millar has collected an unprecedented triple-double - the 100-200m double at the past three national championships - but a back injury ruined his campaign this year.

'I'm stoked and relieved to have won,” adds Kodi, 'although it would've been far better if Joey had been there as well. It probably would've been a different story too.”

'I feel for the guys who should've been there so it doesn't quite feel like a proper championship win but I guess it's in the record books.”

*The New Zealand surf lifesaving championships start on Thursday at Midway Beach in Gisborne and finish on Sunday. Nearly 1500 competitors are expected to attend.