BELO HORIZONTE - One of the great World Cup success stories has been the "magic spray" used by referees to keep a defensive wall 10 yards from the ball at free-kicks but its inventor says he is more concerned with the good of the game than making millions.

Heine Allemagne, 43, who has given Fifa free use of his invention at the finals, says he is driven by a love of the game and helping referees keep discipline rather than becoming a multi-millionaire.

And his invention could hardly be more simple. The referee sprays a line of biodegradable foam derived from vegetable oil in a line on the pitch indicating where the players must stand at a free-kick, and that line disappears within a minute or two.

"I had no commercial ambition, I wanted to develop the product. Perhaps there will be some financial side but that can come later, I wanted to get the product perfect for football.

"I wanted to help the referees keep discipline. The time now taken at free-kicks has dropped from 48 seconds to around 20 seconds. There are less yellow and red cards and more goals from free-kicks, and the players respect the line."

Although the spray cans are not yet widely available Allemagne said the retail price would be around $5 (about R55).

Fifa took delivery of 320 cans for the 64 World Cup matches.

One of the more intriguing aspects of his story is the time it took for such a simple concept to become accepted. Allemagne was working in TV and graphic design when he came up with idea 14 years ago.

Local football authorities welcomed it in the early stages, but Fifa president Sepp Blatter and secretary-general Jerome Valcke needed some convincing later.

"Some people needed convincing, like them. Blatter was sceptical in the beginning but then realised this solved a football problem.

"Some people did not think it was necessary or would act as enough deterrent to keep people behind the line. But they changed their minds." - Reuters