Michael McVeigh from Rossguill Charters spotted the vessel floating out of thick fog near Downings Harbour in County Donegal last week.
When he sent two divers onboard they found rotting vegetables and the email address of its owner on a table.
The yacht was found to be from the Azores islands in the middle of the Atlantic.
Recalling the eerie experience of discovering the boat, Mr. McVeigh said it was only when he was contacted by Malin Head coastguard, a number of hours later, that his initial fears of a tragedy were laid to rest.
“If you find a boat floating at sea, you always think the worst,” he said.
“You always think there is going to be a dead body on board, someone has fallen off and they have died, some poor person is going to be told a loved one is dead.
“It is never good to find a boat floating unmanned at sea.
“I called Malin Head coastguard, they were at an incident working around Portrush (in Northern Ireland). “They said they were busy and would get back to me.
“I took the yacht in tow and headed towards Mulroy Bay.
“It took me a few hours, it was fairly late before we got back in.
“The coastguard came back to me when things had quietened down and they said a lone sailor had been rescued by Falmouth Coastguard probably about 600 miles west of Galway.”
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