EMERGENCY services raced to Fisherrow Harbour at Musselburgh after a man fell from the east pier on Sunday afternoon.
It is believed the man staggered back three or four steps, fell backwards into the harbour on to a speed boat and then fell into the water at about 2.30pm.
It is thought he was pulled aboard the boat by the owner.
One sailor, who was on his boat in the harbour at the time, spoke of hearing a "bang".
A spokesman for the Scottish Ambulance Service said: "Two ambulances responded to an incident at Fisherrow and a patient was safely transferred to Edinburgh Royal Infirmary."
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