Todd Vercoe slogged for three hours through rough seas, thunderstorms, lightning and the threat of sharks.
When he finally reached land he etched "SOS" in the sand with his foot in the hope rescuers would see his plea for help.
It might sound like a scene from a castaway movie but the life-threatening experience was real for the keen sailor, who thought he might not survive the exhausting swim off Northland's coast on Saturday. Still shivering, wrapped in blankets and sipping a hot coffee at Whangarei's St John Ambulance base an hour after being rescued, Mr Vercoe, 36, a house painter from Langs Beach, recounted his ordeal.
He was one of three aboard a nine-metre steel-hulled sloop that left the Bay of Islands about 8.30am on Saturday, destined first for Tutukaka, then Whangarei.
"We had the boat on autopilot and were motor sailing to keep the speed up to make it into Tutukaka before it got dark," Mr Vercoe said.
He estimated they were about 9km offshore when he had decided to relieve himself off the back of the yacht.
"That's when I fell in. I was yelling and screaming as soon as I hit the water. But there was no way they could hear me over the motor and they were both in the cabin below deck."
He watched the yacht continue into the distance, leaving him with the choice of staying put in the chilly water or swimming to shore. He was not wearing a lifejacket. "I thought if I stayed there I'd just freeze so I decided to start swimming. It wasn't too bad because I had a beanie and a polar fleece on."
As Mr Vercoe breaststroked toward shore and swam through a thunderstorm he said his biggest worry was sharks. "I kept saying to myself, 'Don't give up'. I wouldn't say I'm the strongest swimmer either.
"At some points I didn't think I was going to make it. I just kept pushing myself to get there. It was pure will really."
Eventually he had scrambled on to rocks at Rimariki Island but decided he needed to keep swimming to Kaituna Bay, just over the hill from Mimiwhangata Bay.
He pulled himself ashore and used his foot to write "SOS" into the sand. While swimming he had seen the Northland Electricity Rescue Helicopter searching. The others on the boat had raised the alarm as soon as they discovered Mr Vercoe had gone overboard. The National Rescue Coordination Centre had dispatched the helicopter crew about 4pm and Tutukaka Coastguard and another vessel were also sent to search for the sailor.
Rescue pilot Russell Procter said the crew had decided as light was fading it was time to gear up to continue the search in the dark. They had been about to land in the small bay to put their gear on when they saw a man waving frantically next to a plea for help in the sand.
"It was a relief to see them. I don't want to do that again," Mr Vercoe said. He said the experience had been a salutary lesson to always wear a lifejacket.
Intensive care paramedic Mark Going said Mr Vercoe was suffering from hypothermia and was flown to the Whangarei St John base where he had a hot shower, was wrapped in blankets and drank hot coffee to raise his body temperature. He received treatment for a small cut on his foot.
The Northern Advocate contacted the crew on the boat yesterday about midday. They were relieved to hear their crewmate was safe and were looking forward to seeing him again.