In a match as first referee, the Libero was #5 in middle back. A sub wearing a jersey with #5 on it came to the line to substitute for the right front. I signaled for illegal sub and refused entry for the sub. What is the proper procedure to allow the sub to play (–i.e. change jersey number)?

Answer: First let me say kudos to you!  This was great court awareness on your part.  You were absolutely correct in not allowing a substitute with a duplicate number to enter the match.  USAV 4.3.3 is very clear in stating that duplicate numbers are not allowed.

USAV 4.1.3 b does allow for a roster change at any time during a match to correct a uniform number.  The rule also states that when a uniform number is corrected (changed) that team will be charged with a “delay penalty”.   In region play, the player could change uniforms right there, and be allowed to substitute in during the next dead ball. At USAV national tournaments, where rosters are used, the coach would need to go to championship and make the roster change before the player would be allowed to play.