The boundary line defines sport.  Beyond it, different rules apply. It's a different version of life to the one in the office or the street. It's an environment where jarring collisions can occur, where cars can be driven as fast as is technologically possible, where a hard projectile like a cricket ball can be pitched short so that it rears at a batsman's head.

From the time I was a boy, I was thrilled by the skill and daring of players in games like football and cricket. That, in a nutshell, is the fascination of sport for me. Australian football is periodically described as a dance, but it is a dance which requires the players to not only possess timing, technique and balance but also to deliver them under the fear of being tackled and rudely driven into the earth. Sporting performance for me comes back to the old Ernest Hemingway quote that courage is grace under pressure.

This is not to say that sports don't have to adapt and evolve. A case in point is the "shirt-front" which crept into Australian football during World War II. Young men who, for one reason or another, were not on active service fighting the war sought to test their courage by making the game a lot more dangerous.

The old rule, which said you could bump within five yards of the ball, presumed the players were running alongside each other. Now it was reinterpreted. If a player had his head over the ball he could be bumped by a player running flat out from the opposite direction. Bones were broken and players were knocked out. They were, as it was then termed, split down the middle.

The shirt-front had champions who argued it was essential to the game. Possibly its last great exponents were Dermott Brereton and Byron Pickett but, by the early 1990s, it was apparent that the game had changed in a way that made the shirt-front even more dangerous.  Footballers were becoming quicker and stronger and hitting with greater impact; players on the receiving end of shirt-fronts were being left with injuries consistent with motor vehicle accidents.

The shirt-front was legislated out of the game to the extent that blows to the head are now punishable even when unintentional. But AFL football remains an exciting game, one that still demands great courage of those who play it.

The death of Phillip Hughes has left cricket in a curious state of limbo. I would argue that risk is an essential ingredient of Test cricket. Batsmen armour themselves like knights and go out to joust with the great fast bowlers. I well remember the Waugh brothers holding out against South African fast bowler Allan Donald one day at the SCG. Donald hit them with everything. The brothers stood their ground, grimly chewing on their gum, eventually outlasting him. The loss of the shirt-front didn't fundamentally alter Australian football for me; the loss of the bouncer would change Test and first-class cricket. It would become a game like tennis.

There is now a strong move to take the risk out of sport. In August, the Telegraph newspaper in London ran an opinion article which broadcast the opinions of Allyson Pollock, professor of public health at Queen Mary University of London, a former "rugger mum" who claimed that schoolboy rugby players in England now have a one-in-six chance of serious injury every season. She was calling for an outright ban on scrummaging and tackling in schoolboy rugby.

But there are all sorts of cultural contradictions here. On the same day as a woman on its opinion pages was demanding "hands-off" rugby for boys, the Telegraph sports section ran the headline: "England Women's Rugby Union World Cup winners to be paid to play".  The women players were delighted. One of their number, special needs teacher Becky Essex, said, "It's great rugby is taught in schools now and I hope girls aren't still put off by the notion it's somehow risky. The benefits far outweigh any possible risk of injury."

Young people being injured in contact sports is a serious matter but so is the number of young people nowadays said to be afflicted with anxiety and fear of going out into the world. Maybe they need to have a few adventures, to experience a bit of life's rough and tumble, to give a bump and take one, to experience the robust character of the friendships which can grow from physical adventures like contact team sports.

As for the game of Test cricket, the opinions I am most interested in hearing are those of the players. Because this is a critical moment in the game's history, I hope they are not only talking among themselves here in Australia but also internationally. If an injury such as Phillip Hughes' occurred in an international match being played in bad spirit, the results could be dire.

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