One out of Jake Ball, Tom Curran and Mark Wood will replace Overton. Ball has been in the squad all along, but injured his right ankle in the second warm-up game in Adelaide and went into the first Test undercooked after only 15.2 overs on tour; Curran was added to the squad after Steve Finn had injured his left knee shortly after arrival in Perth but may have overtaken Ball; and while Wood could not be selected for the original squad, because of his ever troublesome left ankle, he has trained well enough with the Lions to be drafted in after the third Test. Wood is short of match-practice though, and of the stamina needed to come back for a fourth and fifth spell, which England's pace bowlers have had to do, though not Australia's.
To make another change, and a voluntary one, by bringing in Mason Crane for Moeen Ali, would be a mistake. Moeen owes England's runs and is acutely aware of averaging only 19. His bowling has been even less effective than most English offspinners in Australia but he has been tidy in several spells. Crane would concede more than 3.29 per over to judge by his bowling in the three warm-up games when he would invariably begin well but, after a few overs, his patience would falter and he would lapse into more and more long-hops - and how can a 20-year-old legspinner learn how to construct long and subtle spells if his game-time with a red ball is confined to April, early May and September?
It is 40 years since the famous Centenary Test in Melbourne, which in turn marked the first of all Tests. The Australian survivors - of the 1977 game, that is - will be presented to the crowd at the lunch interval on day three. If this sounds like a mildly interesting historical footnote, in the context of a debate about bouncers it is topical.
In the Centenary Test Bob Willis broke the jaw of Rick McCosker. McCosker returned from hospital to bat in Australia's second innings with his jaw wired up, swathed in bandages, his cap perched on top - and 40 years on, now chaplain at the port of Newcastle NSW, he says his jaw still clicks. When England batted, Derek Randall was hit on the head by Dennis Lillee, doffed his cap and carried on.
The law on intimidation was devised for this era before helmets - and before bowling machines. In 1977 international cricket was essentially amateur: all of England's cricketers were professionals, but players around the rest of the world were mostly weekend amateurs who were paid when they represented state or country. A no-hoper of a batsman even by weekend club standards, like Jim Higgs of Australia or Bhagwat Chandrasekhar of India, got into Test sides. They needed protection by the Laws and by the umpires enforcing them, because the risk of physical injury was distinct.
Since the 1980s, in the era of full-time professional cricket worldwide, young players have been able to - forced to - develop their reflexes against bouncers fired by a bowling machine. Higgs and Chandrasekhar never saw outright fast bowling until they played Tests; now everyone does. There are no no-hopers. The limitation of two bouncers per over is a sufficient addition to the Laws. Australia's Jackson Bird, expected to replace Mitchell Starc with his bruised heel, and a similar seamer to Chris Woakes, said he expects to cop his share of bouncers at number eleven.
James Anderson, after being hit by Starc or Pat Cummins, has not backed away: he has tended to move inside the line, overcoming his instinct for self-preservation, and let the ball go down legside. Thanks to the technological advances since the death of Phil Hughes in extending the protection afforded by the helmet further down the neck, and narrowing the bars of the helmet so a ball cannot pass between, any Test player can protect himself from any foreseeable serious injury.
But Broad admitted to nightmares after he was hit by a ball passing through the bars in 2014. Perhaps the law should be extended so umpires must intervene if there is a risk of physical OR psychological damage.
