The dark arts of the front row By Jeff Probyn Former England international

Probyn played 37 times for England

When England meet South Africa on Saturday one area where there will be no quarter given is in the scrum.

The physical pressures involved in a scrum are immense.

The average front rower at international level has two to two-and-a-half tons of pressure going through his body, so you have to get your angles right.

You also have to get your binding - the way you grab onto your opponent - correct.

Your role is not only to transmit the power that comes from behind you, you also have to divert power that comes at you.

You use various methods to do that.

You can turn your body at a slight angle, or you can bind high or bind low, or you can use the position of your feet - it is the diverting of the pressure that causes or solves problems.

You have to have the ability to use people around you.

In some ways the biggest props are not necessarily a good thing. An example of that are the South Africans.

South Africa like their props on the large side

They tend to have very, very big men in their front row - like the Ollie le Rouxs and the Os de Randts in the past - who are 6ft 3in, 6 ft 4in and around about 20 stone.

The problem is, if you go to that sort of size, you give away flexibility.

You are going to play one sort of game, which is the power-play game.

The front row of a scrum can be a technical area as well as a power area, and if you can use technique against power you are always going to win.

You also need a good, big second row behind you and I was very lucky.

I had Wade Dooley, who was an enormous character, and I had Martin Johnson - he played his first game behind me.

Johnno is another one of those players, like Wade, who can push his bodyweight and more, and if you've got that coming through behind you it's very easy to divert that pressure and put it through the other player's neck and body so as to create pressure on them.

I played at tight-head for England, and there is an enormous difference between each of the three roles in the front row.

Academy guide: Player positions

The simplest way to define it is to say the loose-head prop tends to be a defensive player, the hooker is a primary ball winner and the tight-head prop is a destructive player.

The tight head's job is to disrupt the platform created by the opposition loose-head to enable the hooker to strike the ball.

The loose-head is there to create a platform for the hooker, and the hooker is there to strike for the ball.

The way the components work together against an opponent is the crucial aspect of the game, because if you can't win your own ball at a scrum then you are not going to win the game.