The board rises, a player jogs toward the touchline and the television graphic changes. Those visible moments announce a substitution, but the legal change of player has a defined point in the procedure.
Under IFAB Law 3, the substitution is completed when the substitute enters the field of play. The procedure includes informing the referee and obtaining permission; displaying a number does not by itself make the waiting substitute a player.
Watch the sequence, not only the graphic
At the next substitution, follow the outgoing player, the referee’s control of the change and the incoming substitute. Broadcast graphics can appear before the procedure finishes, and the camera may cut away from part of it.
The distinction explains why someone standing ready at the halfway line cannot simply step in because the crowd expects the change. Entry and exit remain part of an organised procedure, not an informal exchange between teammates.
Keep the competition’s arrangements alongside the law
The permitted number of substitutes, substitution opportunities and special protocols depend on the applicable rules. Current competitions can also implement timing provisions. Check the edition and competition regulations before using a remembered rule to judge an incident.
A useful viewing note has four entries: the stoppage, the official signal, the outgoing player’s departure and the substitute’s entry. If the broadcast misses one, mark it as unseen rather than filling the gap with an assumption.
This also helps when reading match data. A recorded substitution minute is a convenient event label; it does not necessarily show every second of the procedure. For a disputed incident, use the law and the complete sequence rather than treating a scoreboard timestamp as the final authority.
Once these moments are separated, an apparently slow change becomes easier to follow. You can see what has been requested, what is still being controlled by the officials and when the team actually has its replacement player on the field.