Referee Carlos Vera from Ecuador, bottom, uses vanishing spray to mark a line as, from left, United States' Juan Pablo Ocegueda, Javan Torre, Shane O Neill, Mario Rodriguez, William Trapp and Daniel Cuevas form the defensive wall during the Under-20 World Cup Group A soccer match between France and the U.S. in Istanbul, Turkey, Monday, June 24, 2013. FIFA announced that referees at the 24-team tournament in Turkey are using vanishing spray for the first time. It marks a white line on the grass where teams defending a free kick must stand - stopping the defensive wall moving forward or changing the angle of the free kick. The spray is non-contaminating foam that can be used on grass, synthetic and dirt pitches. It disappears between 45 seconds and two minutes of being applied and will be used on a trial basis in all 52 matches of the tournament. (AP Photo/Gero Breloer)

The world’s best football players will literally have to toe the line when defending free kicks in the World Cup.



A water-based, foaming vanishing spray, has been passed by Fifa to help referees keep defenders behind the 10m line and from moving the ball from free kick positions.



The biodegradable white substance, Aero Comex Futline, will be sprayed on the pitch to mark where free kicks should be taken from and the distance the opposition’s defensive wall must observe. The substance dissolves within a minute and leaves no residue.



The sport’s dead ball maestros – your Messis, Yaya Toures and Ronaldos – are devastatingly accurate with free kicks, and many pundits around the world believe the spray will go some way in protecting them from defenders shuffling the defensive wall forward to lessen their chances of getting the ball over the wall and into the net.



The spray is manufactured by Mexican paint company Comex.



It is an “anionic surfactant” – negatively-charged ion molecules which react with compounds in water to produce foam.



A similar sort of technology is used in the production of cosmetics such as shampoo and foam fire-suppressing agents.



Pundits have welcomed the innovation, but others have branded it a waste of time and called for more advanced video technology to help referees.



Dudu Thabethe, a referees executive committee member with Safa in eThekwini, said any technology to help referees in making correct decisions was welcomed.



She raised concerns however, that the technology was not piloted during the World Cup qualifications.



“The problem of encroachment has always been a problem for referees, but we believe the vanishing spray and goal line technology will assist the match officials. The intention is good, but why was it not piloted during the qualifiers?” she asked.



Thabethe said although it might be “exciting” innovation, she wondered “if it will really help” in the problem of encroachment.



International sports agent, Mike Makaab of Prosport International, said the spray was not necessary.



Makaab said he was more interested in seeing the implementation of goal line technology at the World Cup. “It’s a nice gimmick, it adds a bit of razzmatazz for the referee to spray the grass.”



Sharan Singh of True Ambitions Sports Management, said the vanishing spray would help referees as they faced a tough time with players “cheating”.



Singh said video replay in soccer matches was available and should be used by Fifa.



He said local football should use goal line technology and additional referee assistants behind the goals.