Despite the chaos caused by the Australia captain's Covid close-contact disqualification from playing in the Adelaide Test, good captaincy will eventually be defined as "the job Pat Cummins does".
Imran Khan, a fine leader of the Pakistan side before he became prime minister, says in his book, "A good cricket captain must understand bowling." Who better than Cummins - a top-class paceman - to understand bowling?
He is also by far the most inspirational player in the Australia side, and even when he was replaced as captain this week, the team still played hard with thoughts of his reputation in mind.
Cummins acquired the appropriate nickname Postman Pat before he was appointed captain. He is accorded this handle because he regularly delivers, often providing Australia with a wicket when it's needed.
There is a lot to like about Cummins' appointment, and he certainly delivered in his first captaincy Test with a five-wicket innings haul at the Gabba.
Will Cummins have days where it doesn't all go exactly to plan? Too right - that is the life of a captain, and of any leader anywhere in the world. However, Cummins will improve as a captain because that is what good leaders do: they learn from their mistakes and try to avoid making them in the future.
The one question Cummins can't answer is how many Tests he'll miss through injury or Covid regulations. His second-Test hiccup is one he will prefer to have avoided, but having to miss games is something you have to deal with.
Cummins will become a really strong leader and elicit excellent assistance because he's well respected. Eventually he will be ranked as a good leader for all occasions. A lot of that will be based on his calmness and common-sense thinking.
What is the opposite definition of excellent leadership? There's a good chance it can be summed up by Joe Root's captaincy.
Root is an excellent batter but a poor captain. It would not be unfair to describe him as an ordinary and unlucky captain. Rarely do you find a long-term captain who is lacking in imagination but is also lucky. A fortunate captain is usually lucky because the players believe he is some kind of miracle-worker and things tend to work out because of the team's belief.
It showed again at Adelaide Oval that misfortune follows Root's team around. The England bowlers beat the bat regularly but had little to show for their honest toil. However, the England selectors' tolerance of mediocrity was also on view when Jos Buttler, who is far from their best keeper, was again chosen and made yet more inexcusable blunders.
No amount of blustering bluff at press conferences can cover up for the selection mistakes that have been made by England.
It's not that Root's team dislike him - on the contrary - it's just that he has taken so many poor decisions, they must be thinking, "Oh no, not again."
He is not an inspirational captain and this is indicated by the number of times his team work their way into a decent position but can't finish the job. This happened again when, where after conceding 425 in Brisbane, England repeated their mistakes in Adelaide to leak 473 for the loss of nine. Another sign of Root's inadequacy was the number of times he put an English fielder in a catching position following an uppish shot going to that area. A good captain - as Richie Benaud regularly said - is two overs ahead of the game, otherwise he's behind in the match. A responsible leader has a team of competitors who want to play for their skipper.
Root had to find a way to be ahead in the Adelaide Test if England were to surge back into the series. Unfortunately, they again let the opportunity slip with some questionable bowling and even more negative tactics. The dreaded conclusion; "Oh no not again," is likely to be a regular comment while Root remains in charge.