Hoffenheim coach Julian Nagelsmann has defended Sunday's opponents, Red Bull-sponsored RB Leipzig, and compared the unpopular Bundesliga new-boys to the rise of software giants Apple.

Founded in 2009 when the Austrian energy drinks manufacturer bought their licence, RasenBallsport Leizpig has earned their place in Germany's top flight with four promotions in seven years.

They will make their debut in Germany's top flight at Hoffenheim, but the new boys are already immensely unpopular with football fans across the country for the commercialism they represent.

They will be the fourth commercially-backed team in the Bundesliga, along with VfL Wolfsburg (sponsored by VW), Bayer Leverkusen (backed by pharmaceutical giants Bayer) and Nagelsmann's Hoffenheim, backed by software billionaire Dietmar Hopp.

Their mere presence in Germany's top flight has evoked a strong 'tradition against commercialism' debate amongst fans.

"Of course, there are clubs who draw strong emotions. It's great when fans in Cologne or Moechengladbach sing their songs, like they have for years and years," Nagelsmann told Munich-based newspaper Sueddeutsche Zeitung.

"But we should give credit to the work done by clubs, whether they are recently new or have been around for decades.

"In the business world, when a new start-up arrives on the scene with great new inventions, no one says 'they have no tradition, so this product is crap and I don't want it'.

"It's seen as a great, young company whose product everyone wants.

"30 years ago, no one knew of Apple, yet today everyone has an iPhone.

"Incidentally, even 'traditional' clubs spend money. 'Tradition' alone doesn't pay the wages of expensive players."

But even the name RB Leipzig has annoyed some fans, because it flaunts the rules drawn up to keep commercialism out of German football.

'RasenBallsport' (GrassBallsport) is a fabricated German word, an unsubtle way for Red Bull to circumnavigate German Football League (DFL) rules that a team can not carry a sponsors name.

Nagelsmann says RB Leipzig deserves respect for having risen through the German league system without splashing out on big-name signings, despite their deep pockets.

"This (RB Leipzig) is a club which also has a sponsor behind it, just like many others," added Nagelsmann.

"They have polarised people, for example, because Red Bull is also involved in extreme sports, but Leipzig (the club) is doing nothing to harm society.

"They are educating talent, helping with (players) personal development or school studies.

"When 20 young men work with a discipline and a good team spirit towards a goal, that is much better than when they are just getting up to mischief on the streets."