Lucy Needham, 22 - who had been playing in a tournament in south-east Asia - went into spasm and started drifting in and out of consciousness as the plane cruised at 35,000 feet.
A nurse, Pauline Robinson, answered a distress call from the captain and went to Ms Needham's help. The young woman was placed in the aisle and Mrs Robinson, 48, packed her head with ice and told air crew she didn't believe Lucy - ranked 30th among British women tennis players - would survive the flight back to London.
British Airways staff initiated emergency procedures, jettisoning over 300 tonnes of fuel over the sea, before diverting to Madras, where Ms Needham was said yesterday to be recovering in hospital. She should be well enough to fly home later this week.
Her stepfather John Hobbs said she was still weak and unable to say what had been wrong with her, but it was suspected she was a victim of some sort of virus or food poisoning. Brain scans and tests were still being carried out to try and identify the problem.
Mrs Robinson, of Ravensthorpe, Northamptonshire, was in no doubt Lucy had been critically ill. "It was a terrible ordeal for her. She kept sobbing and asking what was going on."Reuse content