We shook hands, the camaraderie between us as ex-jocks being far greater than that between us when we were competing day by day.

After retiring from the saddle six years before, Paddy had turned his knowledge into a business. He wrote brief but wonderfully entertaining histories of racecourses and races, of racing characters and of great horses, and then sold them as slim booklets in racecourse car parks around the country. The booklets built up into an extensive history of the sport and soon were selling so fast that Paddy had employed staff to do the selling whilst he busied himself with the writing.

He had for years been the keeper of his own unofficial racing archive when, with due reverence from the Jockey Club, the post had been made official and he had been invited to coordinate all the material and documents held in various racing museums around the country. But it was the histories that were his fortune. The slim, cheaply produced black-and-white booklets had given way to glossy colour, a new edition every month. Leather-bound holders for the booklets were a must-buy present for every racing enthusiast each December.

Paddy was a mine of both useful and useless information and, since I had taken up investigating as a career, I had frequently referred to him for some fact or other. In racing terms, Paddy could out-Google Google. He was the best search engine around.

‘What chance do you think Candlestick has in the first?’ I asked him casually.

‘Could win. It depends…’ He stopped.

‘On what?’ I prompted.

‘Whether it’s trying.’ He paused. ‘Why do you ask?’

‘I thought I might have a bet.’ I tried to make it sound normal.

‘Bejesus! Now did ya hear dat!’ He addressed no one in particular. ‘Sid Halley’s having a bet. And pigs may fly, I s’pose.’ He laughed. ‘Now if you told me dat you were having a third eye up ya arse, I might more believe ya.’