What is the role of the fourth official in soccer?

The fourth official plays a multifaceted role in soccer, primarily assisting with the smooth execution of the match. One of their key responsibilities is to manage player substitutions. This includes signaling the referee when a substitution is to take place and ensuring that the correct player is substituted. The fourth official also has the duty of managing the technical area, where team staff and substitutes are situated, ensuring that they adhere to the rules and conduct themselves appropriately.

Additionally, the fourth official is tasked with displaying the amount of added time to be played at the end of each half, as well as signaling any stoppages or other incidents that may require the main referee's attention. While the fourth official does have the authority to replace the main referee if they are unable to continue, this is not their primary function. Instead, their main focus is on maintaining order on the sidelines and facilitating communication between the teams and the match officials.