Jurgen Klopp's decision to take up a job with Red Bull has not gone down well in Germany, particularly not with Borussia Dortmund fans who feel their former boss has betrayed their values.
Red Bull's involvement in German football via their ownership of RB Leipzig is controversial, and has led to protests and boycotts, so many were disappointed that Klopp - not shy about his left-wing values - has accepted the role of head of global soccer with the company.
That distaste extends to his former players, too, with one former charge saying he will have a few frank words for Klopp when they next cross paths.
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Former German international Kevin Grosskreutz worked under Klopp at the Westfalenstadion from 2009-2015, and said on his podcast Viertelstunde Fußball (as reported by Sky Germany): "Somehow it still hasn't really sunk in. I was hoping it was a fake news story. It was a shock, and sad too,"
"But as a fan, I don't have to see him in front of the Sud anymore. When we meet, I'll tell him personally that I think it's crap that he does something like that."
Grosskreutz acknowledges this one point of difference does not ruin everything, though, adding: "He will always remain a friend of mine, that's just a fact. He's always welcome at home."
Red Bull founded RB Leipzig in 2009, taking over the license of fifth-tier Markranstadt to gain admittance to the league, before financing their romping all the to the Bundesliga, which they reached in 2016. In 2018, they qualified for the Champions Leauge.
German fans feel that the club runs contrary to their more socialist view on football ownership, with rules limiting the influence of companies and billionaires through the 50-plus-one rule, which says that the club's members - generally, its fans - must own 50% of the club plus one more vote.
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The Red Bull Arena is often subject of boycotts by visiting fans, as well as other forms of protest: the club reportedly struggled to find domestic teams to play them in friendlies this summer.
Dortmund and Red Bull fans have previously clashed, with Dortmund regularly launching protests when the two clubs meet. Crowd trouble at a meeting between the two sides led to Dortmund being fine and their famous Yellow Wall south stand being closed for a game.