Tottenham manager Harry Redknapp told police he writes like a toddler and paid his accountant handsomely "to look after me", the jury in his trial on allegations of tax evasion heard on Thursday.
Redknapp told detectives three years ago that he struggles with basic literacy, saying: "I write like a two-year-old and I can't spell."
The Spurs boss and his co-accused Milan Mandaric both deny charges of cheating the public revenue during their time together at Portsmouth.
In the taped interviews, Redknapp, 64, said: "I couldn't even fill a team sheet in" and insisted he was the "most disorganised person in the world".
But he insisted to officers: "I am not going to fiddle taxes, I pay my accountant a fortune to look after me."
Redknapp, whose success at Tottenham has seen him tipped as a future England manager, said he had not seen his pay slip in years, adding: "You talk to anybody at the football club. I don't write."
Questioned about an account in Monaco which is the focus of allegations he hid $295,000 (225,000 euros) from tax authorities, Redknapp told police he relied heavily on his accountant to take care of his financial affairs.
"He writes all the cheques for me and my wife. He pays my bills. He runs my life basically," he said.
Jurors at Southwark Crown Court in London heard that Redknapp had made "disastrous" business decisions. He had lost £250,000 ($390,000) in a "very unsuccessful" takeover of Oxford United.
John Kelsey-Fry, Redknapp's defence lawyer, said the losses disproved claims made by the prosecution that the Tottenham manager was a "hard-headed businessman".
Earlier a bank executive told the court Redknapp was the only signature on records for the account in which he allegedly hid $295,000 (225,000 euros) from tax authorities.
David Cusdin, vice-president of HSBC in Monaco between 2000 and 2005, said he recalled Redknapp flying into the principality to open an account.
Giving evidence via videolink, Cusdin said: "I was certainly aware of his visit. It was quite possible that I didn't open the account, it was one of my team, but I was certainly aware of the visit."
Cusdin added it was normally necessary for the client to be present: "In this case, it is a single person on the account... one signature on the account".
Another of his clients was Mandaric, 73, who was Portsmouth chairman and now runs Sheffield Wednesday in England's third tier.
The court has heard that Redknapp named the account 'Rosie 47' after his pet English bulldog and that he allegedly kept it secret from his accountant for more than four years.