Across his 16-year playing career, Diego Demme faced some of the world's biggest clubs like Juventus, Barcelona, Inter, Bayern Munich, and AC Milan. However, one of his most daunting challenges came on August 20, 2016, in a DFB-Pokal match between RB Leipzig and Dynamo Dresden.

Demme was 17 when Red Bull acquired the playing rights of fifth-tier SSV Markranstadt and established RB Leipzig. He was 22 when he left Paderborn, who were closing in on a maiden promotion to the Bundesliga, and joined Leipzig, who were already viewed as pariahs by millions of German fans.

These supporters accused Leipzig of using their corporate backing to undermine Germany's 50+1 rule and outspend traditional eastern German clubs like Hansa Rostock, 1. FC Magdeburg, and Dresden, whose supporters had endured years of financial instability.

RB Leipzig's rise has been met with aggressive opposition

It didn't take long for rival fans to voice their discontent. Leipzig's team bus was attacked with bottles during their first away fixture, and players were spat at and pelted with beer cups. Five years later, as they celebrated promotion, a prominent Leipzig supporter known as 'Mocke' was beaten by four assailants.

They suffered more hostility in 2015: Erzgebirge Aue fans displayed banners comparing Leipzig fans to Nazis, and Heidenheim fans threw fake banknotes at the team bus. After warning Leipzig fans against attending, Karlsruher hooligans entered Leipzig's hotel, forcing them to hire private security for away matches.

In Leipzig's opening match of the 2016/17 season, Dynamo Dresden ultras smuggled a severed bull's head into the stadium and hurled it towards the pitch, in protest against Red Bull, whose logo features two charging bulls. Dresden were fined €60,000 and sanctioned with a partial stadium closure order.

Some fans unfurled banners stating that 'tradition cannot be bought.' Another threw a coin that struck Leipzig captain Dominik Kaiser's shoulder, who, after squandering a two-goal lead, missed Leipzig's fourth penalty in a 5-4 shootout defeat.

"We always had fans against us and our project with Red Bull, particularly in the second and third division, and we wanted to give our best to shut them up," stated Diego Demme to FourFourTwo. "Sometimes, there was a little bit of overacting, like when Dynamo Dresden fans threw a severed bull’s head onto the pitch. There were some crazy people, but that gave us a little extra motivation."

If Leipzig thought they would be given a reprieve against Bundesliga fanbases, they were soon proven wrong. In September, 100 Koln supporters staged a sit-in blocking Leipzig's bus and delaying the match. In February, 400 Dortmund ultras gathered before the match and attacked Leipzig supporters with stones and bottles, leaving six Leipzig fans and four police officers injured.

It was Leipzig who had the last laugh, finishing three points clear of BVB in second. Leipzig have finished in the top four in seven of the last eight seasons, and after losing in the 2019 and 2021 DFB-Pokal Final, they hoisted the cup in 2022 and 2023.

Just as Leipzig were gearing up for a run to the Champions League semi-final, Demme left in January 2020. Alongside Yussuf Poulsen, he was the last remnant of a team that had gone from playing in Germany's third tier to sitting atop the Bundesliga.

Six years after swapping Paderborn for Leipzig, Demme departed as a German international and a Champions League footballer. He would go on to win the Coppa Italia and Scudetto with Napoli before enjoying a swansong with second-tier Hertha Berlin.

Leipzig might never win over the hearts of rival Bundesliga supporters, but they did give Demme the platform to win something far more important: his place amongst Europe's footballing elite.