They were discharged in the evening, Max, 22, after treatment for facial injuries, and Jamie, 19, after treatment for shoulder and arm injuries.
The Auckland-based 19ft Sports 200 boat D & H Steel was wrecked and sunk, and was still missing last night.
The crash was likely to end the season's rivalry with the Napier-based Red Steel team of Tony Carson and elder daughter, Charlotte, who had been unable to race on Saturday.
Tony Carson, who operates family business Greenmeadows Panel, witnessed the crash which was captured on an on-board Go Pro camera, and said the boat soared into the air, ripping off its deck as it hit the water.
"It could have been us," he said back in Napier last night. "We were both doing the same speed in the same water."
More than 25 years of race safety training he'd never had to use came into play as he pulled up to the two nephews in the water.
He assessed their conditions before knowing that they had to be taken aboard, their boat having quickly disappeared from view in no more than 10 metres of water.
The race, the fifth of seven legs in the series, with Napier next up on April 22, was stopped and called a "no-race".
Further attempts were being made to find the boat, using new sonar equipment, with the hope of recovering the motor and other gear.
Tony and Wayne Carson won the drivers' championship twice, in 1993 with the 21ft Sleekline boat and National B-class racer ICI Autocolour, the last monohull to claim the national title, and in 1999 with the 32ft catamaran PPG Auto Refinishers, while Wayne, who runs a steel framing business in Auckland, later claimed the title five more times as co-driver with Auckland racer Richard Shores.
In 2008, Wayne Carson escaped serious injury when he and Shores crashed in the champion boat Placemakers at 170kmh in the Auckland harbour race.
He and his brother have in recent years run the two family teams.
