There is incontrovertible evidence to support his claim. On his day he has beaten them all. No lightweight judo player on the planet would dare to treat him dismissively, and apart from fitness, form, class and the side of the bed he gets up on the day the competition starts, there is an overriding reason for believing he can win an Olympic medal.
"My main target in Atlanta is to peak at exactly the right time and fight as well as I possibly can," said the slight, strong Lancastrian. "If I do that then I am capable of beating everyone. They're all going to be physically fit, so mental strength will be vital. If you don't believe you can win then you won't. I believe in myself."
This is significant because the obverse of beating them all on your day is that when it isn't your day you lose. Donohue, still only 26, has been down that road often enough for him to gain a reputation as a maverick, a player who might win with an ippon in the final but who could quite as easily be quickly eliminated, as he was at Barcelona, although injury played a part.
Donohue insists he has learned from those experiences and that he is a more resourceful, less vulnerable fighter because of them. He has also retained his explosive power, his strangle technique and an irksomely - to opponents - unorthodox style that combines judo moves with those learned during his days as a freestyle wrestler.
Most, if not all, of his results of the past two years support his contention that he has matured. He won the European Championship in 1995 and though he came second this year he was still ranked as the continent's No1 on points gained on the tournament circuit.
Sure, he conceded, he was eliminated early and easily in his pursuit of the world title last autumn but his preparation had been disrupted by arriving in Japan too early. He was left bored and with insufficient to do. Donohue places greater importance on his more recent defeat of the man who won that title, Nikoli Ojeguine. He was also particularly careful to take succour from his European championship defeat to Georgi Vazagachvili, whom he had beaten into second place a year earlier. Winning, he suggested, might have made him mildly complacent.
All his training is geared to being at the zenith of his powers, both physical and mental on Friday 26 July, when the 60kg class is held in Atlanta. To that end his present rest day during a week's training is Thursday, so he is accustomed to being fresh on Fridays. He rises at 7am so his body is fully relaxed and his mind properly alert by 9.30am, the time the fighting starts.
Donohue, whose brother Jason plays rugby league for Bradford Bulls, has been especially careful to ensure he avoids the boredom and the lack of distractions which he feels cost him dear in Japan. The team travels to Tallahassee, Florida, this week to begin acclimatisation, so there is a long gap before the serious action begins. His rigorous schedule will demand attention but he will also continue his correspondence course on fitness and nutrition and sports psychology.
"I don't intend to let my mind get lazy. It's got to have something to concentrate on apart from the judo. Studying will help to expend my mental energy - and my mind is the key to success."
Beyond that, there is a more profound personal reason that dictates his inner hunger for success. "My dad John gave me everything it was possible to in terms of sport. He gave me encouragement, he gave me an apprenticeship in his electrician's business to make sure I had a trade, he gave me time off so I could play and he gave me some money in my back pocket. Three years ago, not long after it went wrong for me in the last Olympics, he died. I'd like to do it for him this time."Reuse content