In a way, Andrew Strauss's tenure as the England captain has been about his relationship with one man. From the moment he took office it has been central to England's progress and, at a rough estimate, Strauss is asked about it at every other interview he attends. For all we know, it is a regular topic round the Strauss family kitchen table.
Under normal circumstances, the association under scrutiny would be that between the captain and the coach, Andy Flower. Crucial though that might have been to England's gradual ascent in the past four years, it is not the one that has mattered or the one that has brought England close to catastrophe. It is Strauss's rapport with Kevin Pietersen that has counted throughout. Pietersen has made sure of that. So far, Strauss has managed to cope, bringing a mature and tolerant bearing to his dealings with Pietersen and his observations about him.
But the latest developments in the England dressing room, which have led to Pietersen being dropped from the side with an uncertain future awaiting, suggest disharmony at least from the place where Pietersen sits. Information about the text messages mentioning Strauss sent by Pietersen to South Africa players might not be accurate in every detail but there is enough substance to them to be sure that they were not entirely complimentary.
In the dark days of January 2009, Strauss fielded questions about Pietersen at his first press conference as captain and he is dealing with them all over again in the dark days of August 2012 as the third Test approaches against South Africa at Lord's. He might have expected it then, because he had taken over from Pietersen in the most unsatisfactory circumstances, and presumed that everything would be resolved three and a half years down the line.
This should be an intensely exciting but happy week for Strauss. The match this week will be his 100th Test, his 50th as captain, both landmarks being set at the greatest ground in the world, which he can call home as a Middlesex player. Yet, as if rampant South Africa were not enough to contend with, he is beset by this imbroglio.
If Pietersen has played his last Test, it is not beyond the bounds of possibility that Strauss is playing his. It ought not to have come to this but if England lose – and it is difficult to tip them to win – they will have lost six Tests out of 11 this year.
Strauss said: "I have got a pretty good relationship with KP and I think he is going to be fine, I think he's going to come back and score a lot of runs for England and be a very important part of the dressing room. It's certainly not a hopeless position by any means and not as bad as people have made out.
"Some people get on better with some than others but what is absolutely crucial is that everyone knows their roles and responsibilities and trust that your team-mate is going to do their best for the team."
That was Strauss speaking at Lord's in January 2009 at the start of his great adventure. Whether he will be able quite to repeat those words in their entirety tomorrow when he has to consider the present kerfuffle is another matter. Knowing Strauss he will be calm and measured and not give too much away. That has always been his approach to Pietersen and everything else associated with the captaincy. There may be a harder edge to some of his answers, however, depending on whether discussions are proceeding about Pietersen's future involvement. In the debate about whether England are right or wrong to have dropped Pietersen (and they are right) it could be said that Strauss and Flower have got this part of the job right. Under their time at the head of affairs, Pietersen has scored 3,037 runs at an average of 48.21, not far short of how he was performing before.
He has had indifferent sequences - before and after his Achilles injury in the summer and autumn of 2009 – and he was as poor as everybody else last winter until he achieved redemption in spectacular fashion one steamy Saturday in Colombo. That matters have become increasingly strained is an open secret. Pietersen, recognising his importance to the team, has issued a list of demands and desires. Flower, at the least, has been perplexed and perhaps partially worn down by it. It may not be the sole reason that his relationship with the media is more distant and acrimonious than it was but it is a contributory factor.
Strauss has probably begun to wonder what more he can do to accommodate his star player – when true star players accommodate themselves. Pietersen may be right to have ambitions for himself and his family but sometimes, as Strauss has discovered recently, it is as though he thinks he is the only player in the dressing room who has to be taken care of.
It is draining because there are other, lesser players who need attention. The phrase that will for ever be associated with Pietersen for as long as he plays, was the one he used in his extraordinary press conference after the second Test at Leeds last week: "It's difficult being me in the England dressing... playing for England."
Somebody long ago should have told him how difficult it is being everybody else around him. It is not helped that his ego is constantly fed on social networks like Twitter by the likes of the TV chat show host Piers Morgan, a lifelong cricket fan who should know better. That sort of stuff merely encourages the belief that there are celebrities and there are the rest of us. Pietersen has fallen for it, nay he has lapped it up. Strauss, Flower and the England dressing room have to manage the fallout.