Further details have been revealed about the experiment with two additional assistant referees to take place in this season's UEFA Europa League group stage.

144 matches
The draw for the UEFA Europa League group stage was held in Monaco on Friday, and all 144 group games will be officiated by six match officials. In an experiment which has been endorsed by football's lawmakers, the International Football Association Board (IFAB), the customary four-man team of referee, two assistant referees and fourth official will be supplemented with two additional assistant referees who will take up positions alongside each goal.

IFAB's consent
At its 123rd annual general meeting in Newcastle, Northern Ireland, on 28 February, the IFAB, composed of representatives from the four British football associations and FIFA, gave its consent for the experiment initiated in selected UEFA European Under-19 Championship qualifying tournaments in 2008 to continue at professional level. The choice of the new UEFA Europa League as the competition for this next phase was confirmed in May.

Two extra pairs of eyes
"In essence," a joint statement by world football body FIFA and UEFA said on Friday, "the additional assistant referees will provide two extra pairs of eyes to monitor the game and ensure that the Laws of the Game are upheld, informing the referee of incidents of any kind that he may otherwise have missed, particularly in key areas of the field like the penalty area and its surroundings. The referee will remain in sole charge of the match and the only match official with decision-making powers."

Radio communication system
"The additional assistant referees will be positioned on the opposite side of the goal from the assistant referee – to the left when viewed from the centre circle. Using a radio communication system to relay their recommendations to the referee but without flags, additional assistant referees will generally remain behind the goalline but may enter the penalty area when play moves towards the other end of the pitch so as to keep up with the action.

Same nationality
"Given the potentially crucial importance of their interventions on the course of a game," the statement continued, "referees from FIFA's current international list or the highest category at national level (who were aged under 45 on 1 January 2009) will fill the additional assistant referee role. In keeping with existing policy, they will share the same nationality as the four other members of the UEFA Europa League refereeing team to which they are appointed."

Nyon briefing
A briefing for referees and referee observers was held at UEFA's headquarters in Nyon, Switzerland, this week under the auspices of the guardians of the Laws of the Game, the IFAB. The 48 referees and 48 observers appointed for the 2009/10 UEFA Europa League group stage were given extensive instructions and guidelines by refereeing instructors in preparation for the launch of the experiment when group matches kick off on 17 September.

Expert monitors
"Technical experts appointed by the IFAB will monitor developments throughout in order to assess the impact the two additional assistant referees have on the game and to determine whether they enhance the officials' control of the match," the statement concluded. "The conclusions will later be presented to the IFAB for consideration."