A man thrown out of a boat in rough waves at South Beach "would have been a goner" if he hadn't worn a lifejacket.
Graeme Houlahan, who was running a kontiki fishing rig at the beach yesterday morning, saw two men he knew heading out in a rubber boat.
He said a wave rose up "like a straight wall, basically" and threw one of the men into the sea.
Watching, Mr Houlahan said waves were breaking on top of the man, and the boat would not have been able to reach him easily to help him because of the turbulent water.
The man was "bloody lucky" he was thrown within reach of Mr Houlahan's kontiki, a motorised fishing system designed to pull long lines out from the beach.
The man was able to grab hold of the kontiki and hang on before being rescued by Mr Houlahan, who said the man would have been about 700m out from shore.
"The boat all but flipped ... it got full of water."
He said if the other man had tried to reach his friend, "you would have had two guys in trouble out there instead of one".
Mr Houlahan hoped the incident would bring awareness to people about dangers in the water.
"For God's sake, on this blimmin coast be careful ... check your weather, check your sea."
It was lucky both men were wearing lifejackets, he said.
"He would have been a goner without it."
There have been eight deaths in the water in New Zealand since Christmas Day, including a drowning in Whanganui where a 17-year-old boy was caught in a rip.