New Zealand's leading ocean water swimmers have taken full advantage of the absence of the internationals, with Kane Radford and Charlotte Webby convincingly winning the State Capital Classic in Wellington, round three of the State New Zealand Ocean Swim Series.

The men's race was expected to be a close affair between Radford and Auckland's Phillip Ryan, after a tight battle at the New Zealand Open Water Swim Championships in Taupo this month.

But today was a one horse race, with Radford's aggressive tactics at the start paying off.

"After kind of holding back a bit this year, I thought why not go hard from the start this time and see how it goes. It turned out great, it was my own race," Radford said.

Radford quickly built a big lead and powered away. He won by 53 seconds. He joins Australian's Trent Grimsey and Ky Hurst as race winners so far in the six race series.

Each swimmer's leading three efforts count towards the series, with double points on offer at the final race in April, the State King of the Bays. That makes it the most important of series.

$20,000 is up for grabs for the series winners.

"If I can pick up one more win, it'll all come down to the King of The Bays. It's going to be an interesting series."

It was a similar story in the women's race, with Taranaki's Charlotte Webby surprisingly dominating rival Cara Baker. After swimming together at the start, Webby moved into overdrive at the 1000m mark and won by just over a minute. Her victory was a big boost for her, after some disappointing efforts at the NZ Championships two weeks ago, which Baker dominated.

"I was lacking confidence before going out, because my last two ocean water swims haven't been great. So I was hoping to have a good race, and I'm really happy about it," Webby said.

The women's series is now nicely set up. Webby has won two of the three races, and Baker one.

Overhead conditions for today's 3.3km races were glorious in Wellington, the water though was slightly choppy.

The next race in the series is the State La Grande Classic in Akaroa, February 23rd.

Results: Ocean Swim Series, Wellington (State Capital Classic)

Men

1. Kane Radford (Rotorua) 38:09
2. Phillip Ryan (Auckland) 39:02 (+0:53)
3. Ben Campbell-MacDonald (Wellington) 39:22 (+1:13)
4. Casey Glover (Wellington) 39:55 (+1:46)

Women

1. Charlotte Webby (New Plymouth) 40:18
2. Cara Baker (Auckland) 41:19 (+1:01)
3. Courtney Carson (Wellington) 43:42 (+3:24)
4. Bridget Maher (Auckland) 45:15 (+4:57)