What are the duties of the 2nd referee?

The 2nd referee stands outside the court near the post, opposite and facing the 1st referee (Rule 24). They assist the 1st referee but have their own jurisdiction, and they replace the 1st referee if needed. They may signal faults outside their jurisdiction without whistling, but may not insist on them.

Authority (Rule 24.2):

• controls the scorer's work;
• supervises the team benches and reports misconduct to the 1st referee, and controls players in the warm-up areas (done by the reserve referee at FIVB, World and Official competitions);
• authorises time-outs and substitutions, controls how long they last and rejects improper requests;
• keeps count of time-outs and substitutions, and tells the 1st referee and the coach about each team's 2nd time-out and 5th and 6th substitutions;
• for an injured player, authorises an exceptional substitution or gives 3 minutes' recovery time;
• checks the floor, mainly in the front zone, and that the balls still meet the rules.

Before each set, at the change of ends in the deciding set, and whenever needed: checks that players' positions on court match the line-up sheets.

Decides, whistles and signals (Rule 24.3.2):

• penetration into the opponent's court and the space under the net;
• positional faults of the receiving team;
• net contact, mainly on the blocker's side, and contact with the antenna on their side;
• a completed block by a back-row player or attempted block by the libero, and attack-hit faults by back-row players or the libero;
• the ball touching an outside object, or the floor when the 1st referee can't see it;
• the ball crossing the net outside the crossing space, or passing over or outside the antenna on their side.

At the end of the match, the 2nd referee checks and signs the score sheet.