Stephen Harmison gets up every morning wondering who the hell he is going to be that day. It must be an awfully tiring way to live. A lion wakes up knowing that he is a lion and will get on with the job of roaring and killing stuff. An antelope knows he is an antelope and will get on with the job of eating grass and running away.

But Harmison never knows on any given day whether he is a lion or an antelope, an eagle or a worm, a man or a mouse. He is a shape-shifter capable of the most prodigious changes and he seems to have no control over them whatsoever. Everything about him is fluid, changeable, unstable.

His height is listed as 6ft 4in, but that’s clearly untrue. Perhaps it’s an average. I have frequently seen Harmison when he has been nine-foot tall. Alas, on the first day of the first Test match in the most eagerly awaited series in history, he was 4ft 2in.

How does this happen? Harmison was clearly looking to have one of his nine-foot days: no one wanted him to be a giant more than he did. But alas, he was bordering on the dwarvine. It was a personal and corporate catastrophe, nothing less.

Starts matter. Notoriously, they matter in cricket. In 2005, Harmison bowled the first over of the series. I remember the crackle and fizz in the air that morning, and also the fact that Harmison was having one of his nine-foot days. The second ball whacked Justin Langer on the elbow — the trainer came on to give him lengthy treatment — and every enthusiast for England cricket said: Hello! We might just have a game on here. And a summer . . .

Come, then, to the Gabba just 16 months later. And once again, Harmison bowled the first over of the day. Fizz, crackle, etc.

And it was not like a different time or a different place, it was like — it was exactly like a different man. A man without confidence, a man without self-belief, a man without power.

Normally, when the first ball of the series gets into the hands of second slip, it is a matter for rejoicing. But alas, the ball went to Andrew Flintoff straight from Harmison’s hand, as wide a wide as you could hope to see in professional cricket.

At once sensing Harmison’s fragile state, Langer then took a calculated risk and went after him. He hit four fours in two overs. He was deliberately chancing his arm and most of these shots were not fully under control. But he found the gaps, and they were not the sort of gaps that could be plugged because Harmison was not fully under control, either. A long way from it. As a result of this pitiless assault on Harmison’s mind, the fast bowler was taken out of the attack after going for 17 in two overs. First victory to Australia; and not, I think, the last.

It was a cruel and brilliant and only slightly fortunate piece of cricket. For Harmison matters. He is needed as the shock weapon, the enforcer, the shatterer of confidence. He can make the best batsmen in the world doubt their own talents, doubt their own mind. But he cannot do it as a matter of will. And it took England into a first-ball crisis.

With Harmison, it just happens sometimes, and when sometimes it doesn’t, there seems to be nothing he can do about it. Sports psychologists will tell you that any player can learn to be a master of his own mind, can learn to play his best sport when he needs it most, that mental training works for the most complex and obdurate of minds.

But Harmison has no more control over his mind than he did over the ball when he came out to set the tone for the Ashes series. He knows that England need him, knows that if he has a nine-foot summer, if he takes 20-plus wickets, England will retain the Ashes. And there was no question of shirking or sulking or not being bothered. He put his heart and soul into the job, but his mind just didn’t follow. And it destabilised the team right from the very start.

Ricky Villa, the former Tottenham Hotspur midfield player, used to tell his team-mate, Ossie Ardiles: “I don’t feel like it today.” But every now and then, he would feel like it; and do things like win the FA Cup Final. He, too, had no control over the feeling-like-it and the not-feeling-like-it: it was something outside himself, something beyond.

He is blood brother to Harmison. Harmison, not feeling like it, set England off on a day of calamity and if no blame attaches for that, we must withdraw all the praise we give him on his too-rare great days. It would be ridiculous to say that the match and the series went out of the window with that first dreadful ball, but it certainly felt like it. England need not a psychologist but a spell for turning dwarfs into nine-foot lions.