Frank Lampard will be delighted to learn that this is the first World Cup in which goal line technology will be used. But this isn't the only new innovation changing the game in Brazil: you may have noticed that referees at this tournament are carrying a can of "vanishing spray."

This isn't a spray designed to rid the field of pests like insects or Sepp Blatter, but an aerosol that ensures fair play during free kicks. The premise is simple — when a free kick is awarded, the ref will spray a circle around the ball. Then, he paces out ten yards and sprays a line where the defensive wall will stand. The spray, which looks a bit like shaving foam shot from a pepper spray can, then disappears within a minute.

The invention, which was first used at the 2011 Copa America tournament, serves two purposes. It stops the defensive wall encroaching closer to the ball (in almost 100 percent of cases, the wall will slowly creep forward when the referee has his back turned) and it stops the player taking the free kick from gaining ground by rolling the ball forward a few cheeky inches.

World Cup referee Howard Webb recently told the BBC that this innovation could lead to more goals from free kicks, and it essentially means that Andrea Pirlo is going to score every single time he has a dead ball placed in front of him.

Vanishing spray is not actually a brand new technology, as it has been widely used in MLS and in South America. Also, FIFA trialled it at both the Under-20 World Cup and Club World Cup last year. Next season, it will be used in the Champions League.

Since the spray is new for many referees it will take some getting used to, particularly when it comes to aiming the can...