The explanation made by guest is not clear for me. I wonder how sidster was able to understand. Here is what wikipideia says: A player is in an offside position if "he is nearer to his opponents' goal line than both the ball and the second to last opponent," unless he is in his own half of the field of play. A player level with the second last opponent is considered to be in an onside position. Note that the last two opposing players can be either the goalkeeper and an outfield player, or two outfield players. Also note that offside position is determined when the ball is touched/played by a team-mate — a player's offside position status is not then altered by them or opposing players running forwards or backwards. It is important to note that being in an offside position is not an offence in itself. Another important point to note is that any player's offside position status is reset when an opponent touches the ball and is deemed by the referee to be in control of the ball. The simple rule is : गोलकिपर र फुटबलको बिचमा अर्को पक्षको खेलाडि छ भने त्यो अफसाइड हुन्छ ।