Mustang uses a web-based referee assigning system from . We utilize both self-assigning and manual assigning as described below. If you are a USSF-certified referee wishing to referee at Mustang, click on the Registration link for details on how to establish an account.

Self-Assigning - In order to facilitate the annual assigning of over 6000 referee positions for Mustang games, we release the majority of the games for referees to self-assign. All regular season D4 and D4+ games are available for self-assign, as well as the D1 & D3 U9-U14 games. GameOfficials enables a system of game difficulty and referee ability levels which limits the games which a referee may self-assign to those within their ability level. This self-assigning system allows us to provide referees with the flexibility to select games at their preferred times and levels while keeping them from self-assigning to games beyond their ability:
  • GameOfficials limits referees to a maximum of 3 games officiated per day. 
  • No more than 4 games may be self-assigned in a 24 hour period (this allows more referees an opportunity to sign up for games).
  • Once you self-assign to a game, in order to be removed from the game you must contact an assignor. If cancelling a game less than 48 hours before the match, you must contact the assignor by telephone.  See the Referee Committee link for contact info.
Here is the game difficulty/referee ability level chart:
Level 2         Level 3                  
  D4P D3 D1       D4P D3 D1              
U9           U9           Newly trained Grade 8 referees are assigned a
U10           U10             Ref level of 2 and Assistant Ref level of 3
U11           U11                    
U12           U12           A level X referee may self-assign to any game
U13           U13             level which is colored in the Level X chart
U14           U14                    
                        To gain experience to advance to the next level,
Level 4         Level 5           refs progress from Green to Red games
  D4P D3 D1       D4P D3 D1     When comfortable in the Red, refs request an
U9           U9             evaluation for a level increase  
U10           U10                    
U11           U11           Evaluation games are D1 games in the Red
U12           U12             at the referee's current Ref level  
U13           U13                    
U14           U14           Passing the evaluation increases the referee's 
U15           U15             CR and AR level by +1  
U16           U16                    
U17           U17           An AR evaluation can be requested to raise
U18           U18             the AR level alone, for AR advancement
U19           U19                    
                        Level 8 referees are USSF Grade 7 or lower and
Level 6         Level 7           may referee any Mustang game  
  D4P D3 D1       D4P D3 D1     LEGEND:      
U9           U9                    
U10           U10               "Easy" games which are generally offer few 
U11           U11               opportunities for referee development
U12           U12               "Moderate" games which offer numerous 
U13           U13               opportunities to develop skills  
U14           U14               "Challenging" games for a referee at that
U15           U15               level      
U16           U16               "Challenging" girl's games   
U17           U17                    
U18           U18               Game levels which do not exist (eg. 
U19           U19               U11 D4P)    
Manual assignments – Some games and tournaments, representing the most competitive and challenging games to referee, as well as games where referees are receiving assessments, evaluations, mentoring, and "special request" assignments, are manually assigned.  Here are the game types and the assigning process for each:
Mustang’s regular reason D1 & D3 games at the U15-U19 ages – Referees are assumed unavailable and must explicitly provide availability through the GameOfficials Availability function. Referees desiring these assignments should keep their availability up to date for a period of 28 days in the future, returning to update it when it changes. The assigning process takes place between 21 and 28 days before the game. Assignments will be released no less than 21 days prior to the game and must be accepted within 3 days or they are subject to being released and reassigned. Assignments for these games will be made based on a number of factors. These factors include the referee’s USSF grade, ability level, fitness, contribution to the Mustang referee program (such as mentoring, history of support, etc), need for developmental assignments (assessment, grade advancement, evaluations, and mentoring) and attendance at In-Service Clinics and other training events.
Mustang’s major D1 and D3 tournaments, the Stampede, Devil Mountain, and Winter Turf -  About six weeks in advance of a tournament, referees are sent an email asking them to submit their availability using the GameOfficials Availability function. Referees are assumed to be unavailable unless they provide availability. About 2-3 weeks prior to the event, the tournament assignors publish the assignments, which are made based on referee skill and availability. After the initial release of assignments, any remaining openings and assignments which are turned-back are made available for self assignment.
Assessments, Evaluations and Mentoring - Referees who need a USSF assessment for grade upgrade or maintenance, or who wish to be evaluated for Mustang ability level advancement, or who wish to be assigned a game for mentoring purposes, should contact an assignor and work with them to identify and be assigned to a suitable game.
Special Requests - Mustang’s assignors will work with referees who have special requests to receive manual game assignments in advance of the games being released for self-assign.  Examples of special requests include:
  • Current players and parents of players who are referees - Often, it is difficult to schedule opportunities to referee around a loaded game schedule.  Mustang wants to help these players and their parents gain more opportunities to referee and will manually assign players and parents to games which fit their schedule.
  • Families/friends who want to work together - There are many "referee families" out there who enjoy being able to work a game together, or referees who want to work games with friends.  Contact an assignor to be assigned games together as a crew.


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