One thing referees have always been told is that they should not play advantage when a player has committed an offence that would result in a red card. This might be a straight red card offence or a second yellow card. The only exception to this might be if a member of the team offended against, is in a position where he is almost certain to score. The offender would then be sent off at the next stoppage in play.
However there have been occasions in the past where the goal that appeared imminent has not happened. I remember a Manchester United player being brought down by the opposing goalkeeper on the edge of his penalty area but the ball spun to Paul Scholes in front of an empty goal. Instead of running the ball over the goal line he opted to kick it and it struck the upright and rebounded into play.
There was also a famous case when the supposedly easy goal did not materialise and the offending player, who should have been sent off, then scored at the other end. The player was showered with congratulations by his team mates, before being shown the red card by the referee.
This now can’t happen. Under the rewrite of the Laws, it is still recommended the referee should not allow advantage when the offending player should be sent off and it still accepts that if the referee feels a goal is about to be scored, he may wave play on. However, if the goal is not scored and before the ball goes out of play, the offending player either touches the ball again or makes a challenge, the referee will stop play and send the player off. The game is restarted with an indirect free kick from the point where the game was stopped.
One of the objectives of the rewrite of the Laws was to make it fairer and certainly here is a case where I think this has been achieved.