One of the most challenging games in a referee's career is to be appointed to an FA Cup semi-final.
The likelihood is that one set of supporters at each game will go away from Wembley disappointed and venting their fury on the match officials.
The referee must prepare well and ensure that each member of his team is in top form.
In addition, there is the prospect of extra time and penalty kicks to determine the winner of these games.
So you match officials, please ensure that you are fully aware of the law if either game goes to what is commonly called a penalty shoot-out.
The You Are The Ref team offers its congratulations and best wishes to the appointed match officials;-
5.15pm Saturday 22nd April
Assistant Referees Stuart Burt and Ian Hussin
Fourth Official Neil Swarbrick
3pm Sunday 23rd April
Assistant Referees Simon Bennett and Steve Child
Fourth Official Stuart Attwell