Searchers have so far failed to find two men whose 15m yacht was located by an RNZAF Orion, wrecked off a Tongan island.
The two men, an Australian and an Englishman aged in their 60's, used a satellite phone to tell a relative in Australia that they had run aground at Late Island on Thursday.
The New Zealand Maritime Rescue Centre says there has been no sign of the men during air and water searches over the past two days.
"The rescue co-ordination centre is now focusing on co-ordinating a land-based search of the island of Late, which is where the vessel has run aground," said co-ordinator Sophie Hazelhurst.
"That search will hopefully take place (Sunday) or Monday at the latest and they'll just do a comprehensive search of the island to make sure the men haven't come ashore."
The men told relatives in Victoria on Thursday that their yacht, the Navillus, was breaking up after running aground.
The ABC reports searchers have found the vessel's hull, debris and an unlaunched life raft, but not the two men.
It was hoped the men made it to Late, but an initial search along its shores found no sign of them.
The NZ Rescue Centre say an RNZAF Orion maritime patrol searched a large area and the crew was confident they would have found the men if they had been in the water.