In this June 6, 2014, photo, a referee uses vanishing spray during a referee's training session in Rio de Janeiro, Brazil. Referees will use vanishing spray during 2014 World Cup to stop defensive walls creeping forward at free-kicks.Hassan Ammar/The Associated Press
Vanishing spray will be used by referees in UEFA competitions this season after its successful introduction at the World Cup in Brazil.
UEFA says the spray will debut Tuesday when Champions League winner Real Madrid plays Europa League winner Sevilla for the Super Cup title in Cardiff, Wales.
UEFA president Michel Platini says "as we all saw at the World Cup, this spray was very useful in helping the referee in free-kick situations."
Referees mark a line on the grass 10 yards from the ball to stop defensive walls encroaching.
UEFA's head of refereeing, Pierluigi Collina, says this stops players shuffling forward in a "penguin walk" to close the distance.
The spray will also be used in the Champions League playoffs, then European Championship qualifiers and Europa League group matches from September.