Balls - one of the most talked-about topics at recent FIFA World Cups.
Who would have thought the design of a football could cause so much bother, but that's exactly what happened four years ago when the Jabulani was launched for the 2010 World Cup in South Africa.
Here's what some of the stars had to say...
Italy goalkeeper Gianluigi Buffon: "The new model is absolutely inadequate and I think it's shameful letting play such an important competition, where a lot of champions take part, with a ball like this."
Brazilian striker Robinho: "For sure the guy who designed this ball never played football. But there is nothing we can do; we have to play with it."
England goalkeeper Joe Hart: "The balls have been doing anything but staying in my gloves."
Argentina forward Lionel Messi: "The ball is very complicated for the goalkeepers and for us [forwards]."
NASA were called in to experiment with the Jabulani that was labelled by Brazil striker Luis Fabiano as 'supernatural'.
They concluded that the the ball swerved and swooped from free-kicks that were struck at over 45mph due to its smoother surfaces, and the movements were more visible from dead-ball situations.
This year, the 12th Adidas ball created for the World Cup, is the Brazuca. The creators say the ball has improved touch and accuracy.
The 12 Adidas FIFA World Cup balls:
Telstar - Mexico (1970). The black and white panel design was so the ball was more visible on black and white television. Short for television star, another version of the Telstar - Durlast - was used at the 1974 tournament in West Germany.
Tango Durlast - Argentina (1978). The Tango design was used for the next 20 years.
Tango Espana - Spain (1982). The Tango Espana was the last genuine leather ball to be used in the World Cup.
Azteca - Mexico (1986). The Azteca was the first fully synthetic World Cup ball.
Etrusco Unico - Italy (1990). The design of the Etrusco Unico was inspired from Italy's ancient history.
Questra - USA (1994). Goalkeepers complained about the ball's unpredictability but it went down well with the strikers.
Tricolore - France (1998). This was the first ball to use colour in its design.
Fevernova - Korea and Japan (2002). The heavily criticised ball was the first to part from the Tango design, which had been used since 1978.
Teamgeist - Germany (2006). The Teamgeist was roundest ball ever, according to the designers.
Teamgeist Special - Germany Final (2006). A special golden Teamgeist ball was produced for the 2006 World Cup Final between Italy and France.
Jabulani - South Africa (2010). Jabulani means 'to celebrate' in Zulu. The ball was produced in partnership with researchers from Loughborough University.
Brazuca - Brazil (2014). The Brazuca is the first FIFA World Cup ball named by fans. The name was revealed on 2nd September 2012 after over one million Brazilian football fans voted.
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