Source: Soccer America - YouthSoccerInsider

A well-executed slide tackle robs the opponent of the ball. In the best-case scenario, the defending player ends up with the ball at his feet, jumps up, and launches a counterattack.

At the very least, the successful slide tackle puts the brakes on the attacker, perhaps by knocking the ball out of bounds. But a missed slide tackle leaves the defender down with nothing to show for it, eliminating him from the play.

Goals happen when a defender ends up on the ground. It's very important for a defender to hold his position to avoid making a badly timed lunge that offers the attacker a clear path.

When a player gets past you and you're still on your feet, it's possible to recover and force him to beat you again. Or you can at least get back to support your teammates.

When you're on the ground, you're useless, and you've given the other team a numerical advantage. Players often place too much importance on stealing the ball when cutting off a dangerous pass -- keeping the opponent at bay -- should be the priority.

My Glasgow Rangers coach Dick Advocaat used to tell the defenders, "Just keep him in front of you. Pressure him and wait for him to put his head down."

When a player puts his head down, that's when he's vulnerable, because he's sent the message that he's about to try something. When a defender forces the attacker to take the initiative, he's won half the battle. If you've held your position, by the time the attacker makes his move, a simple toe-poke can be enough to rid him of the ball.

Often, if you run with the attacker without biting on his fakes, he gets frustrated and coughs the ball up. With good positioning, the defender can force a pass his teammates can intercept or a layoff that doesn't pose immediate danger. Ninety-nine times out of a hundred the defender wins the battle if he keeps the dribbler in front of him.

There are forwards who come at you with an array of tricks. They want you to watch their feints and jukes instead of the ball. These forwards succeed when a defender takes the bait. So keep your eye on the ball and don't sell yourself.

Sometimes slide tackling is necessary -- usually in times of desperation, when you've been beaten and you can only reach the ball by flying toward it with your outstretched leg.

A good slide tackle requires that you make clean contact with the ball before you connect with the man. Missed slide tackles don't just give the opponent a numerical advantage -- they're a leading cause of free kicks and penalty kicks, and cause injuries. And they can also result in a red card if you take down a player who has a clear scoring chance.

Defenders tend to overuse the slide tackle, perhaps because, well, it's fun to glide in and nail the ball as the opponent goes stumbling past you. It's a thrill. In England, after a successful slide tackle, the whole stadium gets up and cheers.

You might not get the hurrahs when you've marked a player so well that he's forced to retreat, but you've done your job.

(Excerpted from "More Than Goals: The Journey from Backyard Games to World Cup Competition" by Claudio Reyna with Mike Woitalla courtesy of Human Kintetics)

New York Red Bulls captain Claudio Reyna played nearly 13 years in the top-tier leagues of Germany (Bayer Leverkusen, VfL Wolfsburg), Scotland (Glasgow Rangers) and England (Sunderland, Manchester City) before returning to his native New Jersey this year to play in Major League Soccer. He represented the USA in four World Cups, and captained the Americans to a quarterfinal run at the 2002 World Cup, where he became the first American selected to the FIFA World Cup all-star team.