Ken Jones: Danger lurks for the footballers who have never learned how to tackle

At a tender age, the centre-forward I'm going to tell you about was, in the critical eyes of his manager, a valuable asset. He was brave. He wasn't quick, but he wasn't slow. He would never be known as a great goalscorer, but he would do until somebody better came along.

Trouble was that hefty types were taking advantage of this willing fellow's good nature, using his legs for target practice. Week after week he came off the field with legs so bruised that they resembled two sacks of peanuts. "It's time you got a reputation," he was told. "For what?" he asked. "Nastiness," came the reply.

It made him kind of sad to think about this. However, he watched intently when two hard-bitten team members gave up their valuable time to deliver an illustrated lecture. The trick, they said, was to avoid making a vicious act look obvious. "If you can persuade defenders that you've lost control of the ball, they'll bite at it," the reluctant pupil was told. "When they do, follow through over the top. Bang!" The pupil looked puzzled. "And you're sure this works?" he said. "Absolutely," one of his tutors replied. "We've been in this game a long time. Just remember to roll the ball up slow. Got it? Roll it up slow."

Soon, an opportunity came to put this despicable measure into practice. He had the ball, there was the defender. The words were in his mind. "Roll it up slow." As he lunged in, the defender came in higher. The crack of a broken leg was clearly heard by other players in the vicinity. Going off on a stretcher, he was heard to say: "Roll it up slow. Roll it up slow..."

Don't worry, I'm getting there. I'm getting to the moment in Saturday's match between England and Slovakia when David Beckham recklessly launched himself at Martin Petras. Watching Beckham go in with outstretched legs the thought that flashed through my mind was: "He's on his way to hospital". Not Petras, but the England captain. The assault for which Beckham could, and should, have been sent off was also one that might easily have ended his season, even his career. "Christ, did you see that?" an old pro said late on Saturday. "If the other guy had..." But fortunately for Beckham "the other guy" didn't. Probably doesn't know enough about spite, wasn't raised in a hard school.

These days, similar incidents occur in practically every game. "Sometimes I wince when players plunge in for the ball," a veteran coach said. "Not a clue about protecting themselves. Maybe it's because the game has become so fast, but most of them have never learned how to tackle. Just imagine the terrible advantage some of the old hard cases would have taken."

Let's go back to the referees revolution that greeted the start of the 1971-72 Football League season. It was rooted in a new disciplinary code designed to reinforce the game's fading spirit: 329 players were booked in the first two months of a purge that was particularly painful to those whose game was based on inflicting pain. As player after player felt the wrath of referees – many for dangerous play, but some for the most trivial offences – the new code provoked anger among the clubs (nothing much changes in football). The cry went up that "manliness" was being taken out of the game.

The men who now found it difficult to play were those whose reputations had been founded on coarse challenge and unchecked physical intimidation. Joe Mercer, then general manager of Manchester City, was quick to make a significant point. "A lot of players with a reputation for toughness are being found out. Now they are being forced to try to tackle properly, it's obvious that they can't tackle at all. They have never learned how."

For then, read now. As any coach will tell you, tackling is difficult to teach. There is no definite technique, although old manuals included a picture of two players poised in similar posture over a stationary ball. The forward hunch of the shoulders. The head down. Knee over the ball. A foot drawn back before driving in. This was the popular picture of what a good tackler looked like.

Nothing was further from the truth. Good tackling is about desire for the ball in circumstances that might not always be favourable. If Beckham cares to think about it, and he should, circumstances were not in his favour last week. Luckily for him, there wasn't a bad man on the other side of the ball.