Sir Alex Ferguson has recalled the ‘lonely and frightening’ time he spent in hospital recovering from a brain haemorrhage when he feared he had lost his memory and his voice.

The 79-year-old Scot, who won 13 Premier League titles and two Champions League crowns during a glorious reign at Manchester United, was rushed to hospital on 5 May 2018.

He admits that after the emergency surgery which ultimately saved his life, he was concerned he would not speak again, or be able to remember anything about his life up to that point.

‘That was a big worry for me,’ he told the Guardian.

‘It happened after the operation when I lost my voice. That was the most frightening part.

‘I knew I was alive but, on my own, I started thinking: “I wonder if they’re telling me the truth?”. The operation was a success but you’re in that loneliness. It can be frightening.’

He started to write down the names of family members and players to reassure himself that he had not lost his memory, and was asked by a speech therapist to write letters, including one to his wife Cathy.

Jason Ferguson, who has made a documentary about his father to be released later this month, said: ‘He’d written to my mum, to me, my brothers and all his grandchildren. They were, basically, goodbye letters.’