England 'kneed' Vaughan in Australia this winter © Getty Images

It takes many qualities to be a really good cricket captain. Authority, passion, insight, foresight, calm, imagination, stamina, killer instinct, and the ability to bring out the best in others. None of which necessarily entails a fit pair of knees.

David Beckham needs to be fully fit if he is to be much use to England, as his torpid displays in the 2002 World Cup confirmed. So, surely, does the man at the centre of the great fitness rumpus of this World Cup, Wayne Rooney. But how fit does Michael Vaughan need to be?

He feels he has to be fully fit. Last month he said: "The last thing I need and everyone else needs to see is a limping Michael Vaughan." Last week he said: "I've said before that the last thing England need is a limping Michael Vaughan."

If the use of the third person is mildly alarming, the desire to get back to full fitness is admirable. So is the wish not to be treated as a special case. Vaughan made a big thing of fitness on his first tour as captain, to Bangladesh in 2003. It was a way of pulling the team together and asserting his authority as well as an end in itself. It has worked for England, leading them to pick players younger than they used to, with a few exceptions for elderly debutant bowlers - Shaun Udal, Jon Lewis and now Glen Chapple.

But the fact is that Vaughan is a special case. The captain has the least physical role in the team. He can be portly like Inzamam-ul-Haq or dumpy like Arjuna Ranatunga. The last man to hold the Ashes urn aloft before Vaughan was a limping Steve Waugh. He had just hammered 157 not out at the Oval in 2001. It wasn't the cleverest move Waugh ever made, and may have led to the dip in form that he then suffered, but it showed what could be done. Australia had just lost a Test under Adam Gilchrist, and Waugh, while having sentimental reasons of his own to play one last Test in England, could see that his team were missing his killer instinct.

England badly need Vaughan to play in this winter's Ashes, and they need his brains and his guts more than his runs. As captain, he has been only a moderate batsman: if you take out matches against Bangladesh, his Test average has been 32. In his last three series, against South Africa away, Australia home and Pakistan away, it has slipped to 29. A pattern has emerged whereby he plays one big handsome innings per series, plus the odd fifty. He has matured into a less extreme version of Mike Brearley: not quite such a genius at captaincy, nor such a struggler with the bat (Brearley averaged 22), but definitely more influential as a leader than a batsman.

In a perfect world, he would not only resume as captain but rediscover the form he showed last time England went to Australia. He made three big hundreds then in a highly unusual style, with a kind of rip-roaring elegance. In the real world, it doesn't seem all that likely to happen again. Vaughan tormented the Aussie bowlers of 2002-03 with two shots in particular: the cover drive and the pull. The fantastic thing about both was the extra dynamism he brought to them. For the cover drive, he went right forward, got down low and threw his hands through the shot. For the pull he lifted his left foot off the ground and swivelled. Both manoeuvres were asking an exceptional amount of his knee. It was his left knee, whereas the present injury is to his right, but even so, when you've had a serious problem with one knee, it gets harder to place those demands on the other.

He doesn't need to. You don't have to be a hundred per cent fit to run rings round Ricky Ponting. Captaincy isn't a case of survival of the fittest: it's survival of the smartest. Without him, England have been in some disarray, using three different stand-ins. Last winter, almost unnoticed, was a tale of four captains, just like the nightmare summer of 1988. This week the original fourth choice, Andrew Strauss, is back in the saddle. He shows promise, especially on the calm and imagination fronts, but as he has said himself, he's not Vaughan.

In last summer's Ashes, Ian Bell played all five Tests, making 171 runs in his ten innings. If Vaughan can manage that, and carry on outwitting Ponting, bringing out the best in Flintoff and giving Pietersen licence to hit, he will be well worth a place.

Tim de Lisle is a former editor of Wisden Online. These days he just edits www.timdelisle.com.

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