Put player in mediaeval style knight armor with sensor that detect various parameter along with laser detection system in the whole stadium to determine specific localized coordinate at all time with super-computer analyzing all movement of player and ball. Offside? computer can produced still image with laser precision and each player suit provide the coordinate so we know where each player really is. no need to draw line whatsover. foul? the suit can detect the motion and speed of the player who commit foul and the impact and contact point straight away. Heck, it can even produce x-ray image instantly. No need for referee at all. If foul is given, the suit will take charge of the player body and when they move to proper position will the free kick taker allowed to move. Any hand being positioned in ball flight path will automatically moved away accordingly, so no more concept of handball, thus no more debate on incidental or intentional handball. Heck, the coach can now control the player suit like fifa. Done.