Jürgen Klopp's rise from Mainz heartbreak to Dortmund double triumph

In the 2002/03 season, Jürgen Klopp's Mainz 05 needed a win in Braunschweig to avoid relegation and chase promotion. The team led 4‑0 before conceding a late goal and losing 4‑1, a match Klopp later described as a bitter nightmare.

After taking over Borussia Dortmund in 2008, Klopp turned the struggling club around. Strategic signings such as Robert Lewandowski, Shinji Kagawa and Łukasz Piszczek, combined with his high‑pressing style, propelled Dortmund to back‑to‑back Bundesliga titles in 2010‑11 and 2011‑12 and a domestic double in 2012, followed by a Champions League final appearance in 2013.