His mate got to shore but he was swept out.
Julian Mantoan from Germany was the first to head into the water after realising something was wrong.
"I saw this guy in the water and all his friends were shouting out - they were too young to help.''
Mr Mantoan, who has spent the last month-and-a-half living and working in Napier as part of his OE, swam out to Joshua and said the youngster, while losing strength, managed to grab hold of him.
"He was not too good and he held on to me. We got near the beach but then the waves came.''
As he was supporting Joshua the first police units were quickly on the scene and officers ditched their boots and vests and dashed into the water to help the pair in.
As did Fire and Rescue officer Mike Bond who had been at the Napier police station at the time he heard the distress calls come in.
"I had the defibrillator in the van and just got straight up there,'' he said.
With police and other members of the public who saw what was happening, he formed a strong human chain which latched on to Mr Mantoan and the tiring Joshua.
"We got him ashore - he hadn't taken in too much water - he's a lucky boy,'' Mr Bond said.
Police praised the rescuers' "heroism'' as Joshua was brought to shore "unresponsive and physically spent''.
After being comforted by people on the beach Joshua was able to get up and walk to the waiting ambulance.
Mr Mantoan said he had no hesitation in taking on the big surf.
"You don't think about that - hey, it's someone in trouble.''
One person at the scene said there were people wandering the foreshore but none were venturing near the waterline after heavy swells rolled in through the day.
He said the boys were just "splashing about'' and playing at the water's edge and got caught out by a wave.
Joshua was discharged from hospital last night.