CRICKET FIRST TEST:WHEN KEVIN PIETERSEN admitted this week to sleepless nights as he wrestled with the demands of leading England back to India, it was enough to bring a slight wince of concern. One captain of recent vintage, Andrew Flintoff, has already suffered rapid overload because of the demands of captaining England. It does not bear thinking about that Pietersen might go the same way.

What prevents too much concern is that Pietersen is a fearful embellisher, a man who naturally delights in the power of theatrical exaggeration. So admiration for a team-mate is expressed in terms of love and affection, a half-decent display is fantastic. We can conclude therefore that Pietersen's sleepless nights are actually just a bit of tossing and turning. England should quietly check it out all the same, because anything else would be a reason to protect him before it is too late.

Almost without comment, he is well on the way to becoming the most powerful England captain for a generation. Michael Vaughan and Nasser Hussain were tough cookies, but they were answerable to Duncan Fletcher, the coach. Pietersen makes no such concessions to Peter Moores. He talks of "my team" and he won the argument for a less intensive training regime than in New Zealand last winter. And, in a major political crisis, while Pietersen has held counsel, Moores has remained in the background.

England's start under Pietersen was perfection: he made a 100 in his first game as captain, against South Africa at The Oval, but from the outset the most noticeable aspect was how enthusiastically England responded to his leadership. He then led England to an overwhelming success in the one-day series.

Even the sceptics were impressed, confining themselves to the sage reminder that the real test of Pietersen would be when the defeats started. The implication was that it would only take a couple of losses before he caught a fast plane to nowhere.

It can safely be said that such a test has now been passed. Pietersen has had to contend with England losing the one-day series in India 5-0, and seemingly heading inexorably for a whitewash before the last two matches were cancelled, and then the fallout of the attack on Mumbai.

To date he has survived everything with near-impeccable judgment. He has behaved in a manner of which few suspected he was capable: he listened, he assessed, he made a rational response.

His decision to walk out on South Africa in protest at racial quotas, rather than fight for his rights in a problematic post-apartheid environment, will always offend liberal sentiments, but he puts his unexpected toughness down to precisely that experience.

"It's been tough," he said yesterday, ahead of today's first Test at the MA Chidambaram Stadium. "I don't mind when the going gets tough because it is more satisfying when you do well."

While Flintoff marched out of - and then back into - India with grim expression, a sportsman in unfamiliar territory, Pietersen's instincts were faultless. He left with a seriousness appropriate to a tragic situation, but when he returned to Chennai he gave a thumbs-up signal to the crowd from the team bus. He might not have known, but it was the same thumbs-up gesture given by Indian commandos when they had cleared the Taj Mahal hotel of the last of the terrorists. Without as much as a single word, it quietly signalled defiance.

Pietersen has also liberated England's players. They might still be losing more than we would like, but their spirit has been strikingly good. Even Flintoff, who was never a soulmate, now speaks fondly of the relaxed atmosphere. Vaughan encouraged England to express themselves, but Pietersen's very persona gives them permission to do just that. He liberates them from their anxieties.

Pietersen has assessed the nature of India with remarkable skill. When he and Mahendra Singh Dhoni, his home counterpart, appeared together for promotional pictures yesterday, in a room far too small and disorganised for the occasion, the Indian media turned the occasion into a scrum that sent England's security man white with shock. In the middle of it all, Pietersen looked amused, bemused, unflustered and unfailingly polite.

He knows there are some things in India that you can never tame. He has been just the man for a crisis. Who would ever have expected that?

• Guardian Service