New Zealand's Braden Currie and the American, Meredith Kessler, have defended their titles at the Taupo half Ironman.
Currie, who sat fifth at the end of the bike leg, surged on the run to clinch a 33-second victory from compatriot Mike Phillips.
In the women's race, Kessler, clung on to claim a dramatic victory by just eight seconds from the fast-charging Briton Laura Siddall.
"Of my seven wins here in Taupo, that was by far the hardest. Laura was so close. Another 100 metres I think she could have beaten me," said Kessler.
"I am thrilled to win here. And now I will recover and prepare to return here in March for the New Zealand Ironman and attempt a six-peat which will be no easy task."
Wanaka-based multisport athlete Currie, said of his win: "I just had to do what I could do on the bike and know that if I could remain within striking distance on the run then I would have a chance.
"I put an effort in to put 200 metres on Mike (Phillips) and I thought I was running well and he would be happy to sit there but he wasn't and it was a bit surprise to see him run up beside me. I took my time and then put down the hammer 5 kilometres out and knew I had to hang on."
Australia's former Olympic rower Todd Skipworth was third.
Kessler emerged from the water in the lead which she maintained after the cylce leg before nearly being caught by Siddall in the final 5km of the run.
Kessler, crossed the line 4:22:35 as New Zealand's Amelia Watkinson claimed third place today in 4:28:24.
Elite men: Braden Currie (NZL) 3:52:44, 1; Mike Phillips (NZL) 3:53:17, 2; Todd Skipworth (AUS) 3:56:56, 3; Eddie Rawles (NZL) 3:57:50, 4; Drew Scott (USA) 3:58:09, 5; Lachlan Kerin (AUS) 3:59:40, 6; Dougal Allan (NZL) 3:59:53, 7; Cameron Brown (NZL) 4:03:14, 8; Paul Ambrose (AUS) 4:04:47, 9; Simon Cochrane (NZL) 4:06:21, 10.
Elite women: Meredith Kessler (USA) 4:22:35, 1; Laura Siddall (GBR) 4:22:43, 2; Amelia Watkinson(NZL) 4:28:24, 3; Rebecca Elliott (NZL) 4:37:57, 4; Laura Wood (NZL) 4:45:05, 5; Tamsyn Hayes (NZL) 4:45:11, 6; Hannah Lawrence (NZL) 4:45:19, 7; Pip Meo (NZL) 4:52:03, 8; Elaine Brent (NZL) 4:53:20, 9; Melanie McQuaid (CAN) 4:56:39, 10.
NB. The Taupo Ironman 70.3 is so called because 70.3 miles is half the distance of a full length Ironman triathlon.