Ironman veteran Garth Barfoot is recovering in hospital with a broken femur after a car hit him while he was out cycling.
Police say it is likely the car driver will be charged with careless driving causing injury.
Mr Barfoot, 77, was riding in Birkdale on the North Shore about 8am on Wednesday when the car struck him, throwing him on to the road.
His daughter Kiri Barfoot told the Herald he landed heavily on his left side and suffered a severe break to his femur which required major surgery.
"He was up the road from where he lives and he was going around the roundabout. He was on the roundabout so he had right of way when a car approached," she said.