Joe Root is a learning captain. There has been no time in this brief life to do much else than play and watch others. He was up close and personal with Alastair Cook: indeed at times he appeared to be Cook's adventure ego. He works alongside Eoin Morgan's cool ambition. He has three times been in the Ashes fray against Michael Clarke and seen an explorative mind for cricket and some examples of Australian hardball. He has clocked that AB de Villiers and Faf du Plessis suffer at the hands of a regulated system. He has noticed the vastly different methods that have characterised MS Dhoni and Virat Kohli. He will have taken in Misbah-ul-Haq's poker face. He must have enjoyed Brendon McCullum's joie de vivre.

Root misses very little. Daily he seeks further information, while soaking up all that is around him. It feels as if he can already identify between good folk and bad. It is not a coincidence that his batting is adaptable, for that is the nature of the man. The best captains see the world outside and put it to good advantage. Only once at Old Trafford - in the middle period of the fourth day, when Hashim Amla and du Plessis were going through the gears - was he truly threatened. The temptation was to retreat and dry up runs but his response was to attack. He switched Moeen Ali away from his successful end to the one now named James Anderson, and placed three fielders around the bat. Soon Amla missed a spinning offbreak and was plumb lbw. Root replaced Moeen at the Statham End with Anderson and positioned two wider slips. Immediately du Plessis thrashed outside off stump and fatally edged. From going through the gears, the engine of the South African team had broken down.

In time, Root may think an extra slip worthwhile while the new ball is moving around. The more he looks at the game subjectively, the more he will see that its bounce demands something as old-fashioned as a short leg (never mind a third man, the position that is gathering dust). Most of the modern batsmen have hard hands and a tendency to press forward. A few runs through square leg are a small price to pay for the bat-pad that pops up to the man on "boot hill".

"To the delight of everyone, Anderson and Broad came pounding in as if powered by Root's electricity. Far from looking as if they were running out of years, they had the spring of a March hare and the hunger of wolves"

Watching the England captain is a joy, a sidebar of its own. His energy is directed towards aspects of the match that matter. He doesn't do peripherals, nor sweat the small stuff. Although his body already appears to creak, rolling as he does from hip to hip in the gait of a much older man, his mind is young, sharp and full of purpose. He improves with each day and has received plaudits from the senior pros, who must have wondered. He will break free of previous influences as he reviews past matches. On the subject of reviews - as in the Decision Review System - he is better than he was in the first two Tests of the series but still needs a lesson, then homework. The use of the system is a skill worth exploring.

For Root the future is clear and, overall, quite bright. He does, though, need a couple of batsmen whose role is identified and inherent in their specific talent. Mark Stoneman should be told to see off the new ball; Alex Hales to thump the old one. That takes care of No. 2 and No. 5; No. 3 is more difficult. Doubtless Tom Westley will get a run at it but his flaws are widely seen and not difficult to exploit. Time with Graham Gooch would serve him well. Meanwhile David Malan sets up well - if a little closed in his batting stance - but does not find it easy to be himself. Belonging is not as straightforward as it looks from afar. He is worth further investigation.

To the delight of everyone, Anderson and Stuart Broad came pounding in as if powered by Root's electricity. Far from looking as if they were running out of years, they had the spring of a March hare and the hunger of wolves. There is a stock of waiting fast bowlers to keep Root believing that Australia can be conquered too.

These choices are bountiful compared to those at the feet of the South Africans. The domestic game back in the republic is not producing the ready-made Test cricketers it did for so long. Dependence on so few is a mighty challenge. Du Plessis' exasperation was clear from the moment Vernon Philander became sick at The Oval. Above all, captains like to feel they can control a game when in the field. This is dependent on four reliable bowlers and safe catching. If at least two of those bowlers are proven wicket-takers, all that is left is intelligent application of these forces.

Du Plessis proved himself a tough and street-smart captain in Australia last November, though precious little imagination was required to outplay a feeble Australian team in the first two Tests. In the third, the day-night game in Adelaide, Australia woke up and South Africa had to think fast. Du Plessis was all over it, reacting to the rapidly changing conditions and making an impressive hundred himself. Afterwards he said he would like to see more Test cricket at night. The pink ball was just fine, he added. All this after his team had lost to Steve Smith's rejuvenated Aussies. The point was that he could see the bigger picture.

That has been harder for him in England and his confusion at South Africa's inability to hang on to the game was clear. Frankly, he would have settled for his team hanging on to their catches. Philander's ongoing absence was crucial at Old Trafford, especially on the first day, when conditions demanded a greater examination than given to the suspect England batting. In the circumstances, 362 was an unjustifiably high total and South Africa played most of the rest of the game as if they knew it.

"The best thing AB de Villiers could do for the country he so clearly loves, and for the game that has given him so much, is summon up the strength to play the home Test matches this coming season against India and Australia"

It was odd to read AB de Villiers' many tweets >commenting on the matches. These sympathised with his countrymen and always urged them to greater things, while occasionally praising England or offering opinion on match situations. The dressing room might have thought: if AB is investing so much energy into this at home why can't he come and play? Du Plessis cannot have found it easy to have his best batsman on the sofa thousands of miles away.

Rumour has it that de Villiers is close to retiring from Test cricket. In general, the game has taken its toll on him. But the best thing he could do for the country he so clearly loves, and for the game that has given him so much, is summon up the strength to play the home Test matches this coming season against India and Australia. Shane Warne retired from one-day cricket early in 2003 so that he could keep mind and body fresh for a final assault on the summit of Test cricket. Four good years and a dramatic farewell came from that decision. AB has so much still to give.

The IPL and other diversions will wait, or can be accommodated in a well-thought-through schedule. South Africans would rejoice in this; we all would. It may be that de Villiers and du Plessis are not in harmony, but that need not cloud the important role that both have in getting South African cricket over the line at a very tricky time. Early next year the young people of their great land will be aware that two important series are taking place, but they may not buy into a team that has lost some lustre. De Villiers is a proper star, a superstar indeed. They will buy into him again for sure. Du Plessis must persuade de Villiers that they can work together for the common good. It is a cliché but cricket in South Africa is bigger than either of them. A memorandum of understanding, if we can call it that, must be agreed and acted upon. AB, this is your moment.