It won't just be the players competing at the World Cup in Brazil, the world's top sporting brands are too. German firm Adidas - the official match ball maker and traditional leader in the soccer shoes and shirts market - is facing a fierce challenge from Nike.

Ready to play a starring role on the pitch in Brazil - and I'm not talking about the players. The Brazuca is the match ball for the football World Cup. It's made by Adidas - the German firm's supplied the tournament's official ball since 1970 and has extended World Cup sponsorship until 2030. Herbert Hainer is Adidas' CEO.

"We're selling millions and millions of balls, then we have the ball boys, we have the referees, we have the billboards, we have nine teams, so we are very, very present. And obviously through our partnership with the FIFA we have special occasions where we as the only sports brand can be, which gives us exclusivity. So hopefully we will have a team which will also win the World Cup." Hainer said.

Adidas is supplying nine teams - including reigning champions Spain, Germany, Argentina. But it's being tackled by a new rival. For the first time, U.S sportwear brand Nike is kitting out more teams - 10 in total including hosts and favourites Brazil. Adidas has traditionally been the top-selling brand in football, and expects to make a record 2 billion euros from the sport this year, whereas Nike predicts it will make 1.5 billion euros.

"This is a head-to-head race between them and us about the market leadership in football, we are still clearly ahead of them." Hainer said.

Nike is also sponsoring some of the world's best-known players. It's signed six of the 10 most marketable footballers in the world - like Portugal's Cristiano Ronaldo - to Adidas' three. And that's where it can get complicated, says Kevin Carpenter, a sports lawyer at Hill Dickinson.

"Lionel Messi plays for FC Barcelona and therefore their kit is manufactured by Nike, however he's sponsored by Adidas, who also sponsor his national team, so you can see how this starts to become difficult both commercially and legally." Kevin Carpenter, sports lawyer with Hill Dickinson, said.

During the World Cup, Adidas has a privileged position as the official sportswear sponsor, meaning Nike needs to be creative to grab attention.

"Nike on the other hand will have tendered for that process, but not won, so they then have a commercial decision to make of how best to avoid the long list of regulations and laws that are in place to prevent what we would term ambush marketing, but I think people are increasingly seeing it as creative marketing." Kevin Carpenter, sports lawyer with Hill Dickinson, said.

Marketing experts won't just be watching the action on the pitch in Brazil - but who comes out on top in the battle between two of the world's biggest sporting brands.