Among Alastair Cook's qualities as the captain of England will be his composure. He will usually act and, on the days he has shaved, look like the choirboy he once was.
But this will pale next to Mahendra Singh Dhoni, his counterpart with India. Cook may be calm, he may be a man who never perspires but compared to Dhoni he will reveal a thousand feelings with every ball that is bowled.
Dhoni is utterly inscrutable on a cricket field. True, as captain he directs traffic from time to time, it being difficult for a wicketkeeper-captain to attract the attention of his men. But he betrays no emotion.
It was instructive to watch him in England last summer when India were being bashed from pillar to post. Anybody asked to tell how India were doing purely from watching Dhoni in business would have guessed that they were holding their own at worst.
It will be fascinating, it always is, to watch the two captains at work in this Test series. There will be long, hot, dusty days in the field for both of them when directing traffic is all that they can do.
Cook is at the start of his great adventure and given the demanding nature of the challenge, recriminations will be few if England fall to India. The manner of their falling would be the significant aspect.
Dhoni, by contrast, is a man under close scrutiny if the media coverage of the past week is to be believed. It is difficult to do so. Winning a World Cup buys you as much freedom in India as winning the Ashes in England, or winning the lottery anywhere. You can virtually name your own retirement date.
Public gratitude is so abundant that the here and now tends to be overlooked.
There is a sentiment abroad that Dhoni has taken India, in Tests at any rate, as far as he can. This has evolved from the two hammerings his side received in England in the summer of 2011 and in Australia immediately after. They lost eight Tests without reply.
If Dhoni is a man feeling the pinch, it was typical that he showed no sign of it whatever yesterday. Perhaps he knows that Tests have ceased to count on the graph. In the Indian public's estimation they are equivalent to a television company bidding for broadcasting rights – worth much less than limited-overs matches.
Dhoni is aware that Test cricket is sliding in public affection and perhaps attention but he made a reasonable fist of defending it without being gooey-eyed as cricketers so often are.
"A lot depends on the economy, the reason being it's very competitive," he said. "Five days in a week makes it very difficult for a large amount of people to come on to the field because it's not very easy to work in the private sector and turn up and say I'm going on holiday, I want to see India play.
"But still a decent amount of people turn in to see the Test matches. We have seen in the smaller cities, we have got more crowds compared to the bigger cities. I don't think it's really alarming. There was a period once when the stadiums were house full when it came to Test cricket. But we still get a decent amount of people in."
Dhoni makes more money than any other cricketer on the planet, including Sachin Tendulkar, estimated to be around $26m (roughly £16.4m) last year. Hardly any of this is because of his deeds as a Test cricketer and captain.
He happens to be one of India's most successful captains of all despite the recent away form. Of the 39 Test matches in which he has led the side, India have won 19, the proportion of victories greater than any previous captain. He averages almost 40 with the bat, perfectly respectable as a wicketkeeper who is now India's most prodigious with 224 dismissals.
It is the World Cup triumph last year that sustains him and may even allow him to extend his tenure should Cook get the better of him in the next month. Dhoni, however, has never lost a series at home. There are genuine concerns about low attendances on most days of the four matches but Dhoni, as in most things, is sanguine.
He said: "Test cricket definitely has a future. I feel it will only improve but it's very important to get children into the Test format. It's a world of fast food where people don't want to wait for an hour to get their order to eat. They're quite happy eating their 20-minute burger."
Dhoni is an old sweat, seen it all, done it all. Cook stands on the verge of something. He is not a man for poetry as his batting demonstrates but he said: "I feel a mixture of everything. Obviously, a bit excited about what's going to happen, a little bit nervous but the overwhelming emotion is that I am very proud to be leading England."