A Decade of Challenge in Volleyball: When Referees Must Reconcile the Rulebook with Twelve Cameras

The ball dropped just inside the sideline. The first referee's whistle rang out: out. The score was 24-23 in the fourth set, and the arena went silent for a heartbeat. The captain spun two fingers in a circle, the signal to request a challenge. Seventy seconds later, the big screen showed a slow-motion frame: the ball touched the line. The point was overturned. No one shoved the referee, no one slammed a hand on the score table. There was only a frame and a rule, projected for the whole arena to see.

That moment is what I have tracked for years, not because it is dramatic, but because it shows how the authority to decide has changed hands. A volleyball referee is no longer the only person holding the whistle. Beside them stands a system of cameras, a closed control room, and a rulebook rewritten to accommodate machines.

The challenge system, officially the Video Challenge System, was first introduced by FIVB at the 2026 FIVB Volleyball Men's World Championship in Poland, held from 30 August to 21 September 2026. It was the first time a world-level tournament allowed teams to ask referees to review a situation on video. The system later appeared at the Rio 2026 Olympics, the Tokyo 2026 Olympics and the Paris 2026 Olympics, along with nearly every edition of the Volleyball Nations League.

The mechanics are simple but strict. Each team is allowed two requests per set. If the request is correct, the team keeps its allowance. If it is wrong, the team loses one. In the deciding set, the fifth, each team has only one. The captain or the coach gives the signal, and the request must be made immediately after the ball dies, before the referee authorises the next service.

The list of challengeable situations is set out in the FIVB Official Volleyball Rules: ball in or out, block touch, net touch, service-line fault, ball touching the antenna or passing outside it, back-row attack fault, and ball touching the floor. Outside this list, referees have no obligation to review.

The cost of the system is not small. A court fitted with enough cameras, servers and a control room demands an investment most national leagues cannot afford. That is why many volleyball nations, Vietnam among them, can only use the system at international events hosted at home, not in the national championship.

For teams such as the Vietnam women's national team, where captain Tran Thi Thanh Thuy regularly plays in continental competitions, getting used to the challenge has become part of the job rather than something unfamiliar.

What is worth analysing is that the system does not merely correct errors; it changes referees' behaviour before anyone requests a challenge. Knowing that every tight line call can be reviewed, referees tend to be more cautious on clear plays and more assertive on ambiguous ones. They shift from a mindset of deciding and owning the responsibility to one of deciding so the system can confirm.

From 2026 to 2026 I recorded figures at the international matches I watched in person. In matches without a challenge system, captains protested to referees far more often. In matches with it, protests almost vanished, but dead time increased. Each review takes forty to ninety seconds. A match with five successful challenges and seven failed ones can stretch by nearly ten minutes.

In net-touch situations the shift runs deeper. Since 2026, FIVB has amended Rule 11.3 so that a net contact is a fault only when it interferes with play. Previously, any touch of the net cord drew a whistle. After the change, a referee must judge whether the contact disrupted the opponent. This is the kind of call a camera cannot make for a human, because it requires reading intent and reading the rhythm of the rally. A challenge can show that a hand touched the net, but it cannot show whether that touch interfered. This is the grey zone technology cannot fill, and it is where controversy concentrates.

Another point rarely discussed: the challenge has become a tactical tool. Teams do not only ask for a review when they believe they are right. They ask for one to break an opponent's momentum, to give the block a few dozen seconds of rest, to disrupt the serving rhythm of a hitter who has found form. In top matches, a challenge is used as an unofficial timeout. The rules do not forbid it, but the spirit of the rules never accounted for it.

I once watched a match in which a coach spent his team's last challenge of the set purely to slow the opponent's serving, even though he knew his team would lose. He did not need to be right; he needed time. And the rules gave him time.

The second referee's position also deserves mention. In volleyball, the second referee stands at the net post, responsible for net contacts, centre-line faults and back-row attack faults. When the challenge arrived, this role became more sensitive. Many net-touch calls made by the second referee go up on the screen, and a single frame showing a hand on the cord overturns the decision. The pressure is no longer about seeing correctly, but about guessing correctly what the camera will record.

This is where I have to push back against much of the praise the challenge receives. Its supporters argue that technology makes the game fairer. That is true for the objective facts: ball in or out, touch or no touch. But fairness does not mean accuracy in every dimension.

There are three consequences few are willing to face. First, authority is split into two tiers: the referee on court and the video operator in a closed room. The second tier has no visible face and no audible voice, yet decides the most important points. Accountability disappears along with anonymity. Second, referees gradually lose the habit of trusting their own judgement. A generation of referees raised alongside the challenge may decide more slowly, wait more, and lean on the screen more than on their eyes. Third, spectators grow used to the idea that any decision can be overturned, so trust in referees does not rise; it migrates to the screen.

I was expelled for reading the rules correctly. Fortunately, some things are only clear from outside the door. From outside the door, I saw that a rule is not right by nature. It is right only when applied consistently, and that consistency is not created by a camera. A camera supplies data. A human is still the one who interprets the data.

When VAR examines a statement, I do not argue. I let the camera bear witness. But in volleyball, the camera is only a witness, not a judge. And a witness who has not been trained can still lie by staying silent, silent about what it did not record.

The direction of the next decade probably lies not in adding cameras, but in rewriting the rules to answer the questions technology raises: who is accountable when the video room errs, whether challenge allowances should be time-limited to prevent abuse, and how to preserve human judgement in the zones machines cannot read.

Rules do not feed people, but people feed the rules with model rallies. A mature volleyball culture is not one without controversy, but one that can point to which rule is being applied, by whom, and on the basis of which frame.