"I got pulled out by a rip and sensed because of the huge waves it would be better if I swim all the way to the beach which took me just over an hour.
"The doctor was in the water for about half an hour."
Mr McPherson reached the beach the same time as a Northland Emergency Services Trust (NEST) helicopter arrived to winch the doctor to safety.
"I just think anyone in my position would have done what I did," he said.
The incident happened just hours after two Canadian tourists were rescued from Rokoaweke Pt, between Whale Bay and Mermaid pools, where they were forced to spend Friday night.
About 9am on Saturday, members of the police Search and Rescue team successfully brought the Canadian tourists down a cliff after they got into trouble about 8.30pm on Friday.
Police search and rescue co-ordinator for Northland, Senior Sergeant Cliff Metcalfe, said the male and female tourists started walking from Matapouri and intended to go to Whale Bay about 7pm on Friday.
However, they took a wrong turn and followed a track in the direction of the Mermaid pools.
After realising they had gone the wrong way, they started walking along the coastline towards Whale Bay but got stuck by the incoming tide.
"They decided to climb on to a ridge and try and walk out but once the tide comes in, it forms an island around where they were so they got themselves in a very precarious situation," Mr Metcalfe said.
The tourists, he said, managed to ring 111 and a police Search and Rescue team and volunteers from Northland Cliff Rescue began looking for them.
They were found on Rokoaweke Pt at 1am on Saturday but rescuers could not reach them.
"They were in effect on an island and we were on the mainland and there was a 50m drop between us and them so we yelled out for them to stay put and we'd reach them at low tide which was about 9am on Saturday."
Mr Metcalfe said the tourists were not in any danger on a warm night although both had light clothing but no water.
They were tired and dehydrated when rescuers eventually reached them.
"We made three unsuccessful attempts from different angles at low tide but managed to get around the rocks on the fourth attempt and bring them down.
"Two of us climbed the ridge line which was no wider than 1m with steep drop offs 40 to 50m on both sides.
"They got in an area which was really dangerous and they could have easily fallen off the cliff."
Mr Metcalfe said 3 to 4m-high waves made the rescue difficult and dangerous.
The tourists were at the end of their six-week holiday in New Zealand and are booked to fly to Australia sometime this week.
Mr Metcalfe said better signs on the dangers around rocks were needed at the entrance to the tracks leading to the Mermaid pools.
He said those that got into trouble while walking the tracks leading to the Mermaid bathing pools and nearby Whale Bay should simply stop and turn back rather than attempt detours and get into trouble.