To be a top coach in German football, it is important to posses a certain amount of self-confidence. "The decisions I make are always correct!" the legendary German trainer Otto Rehhagel used to say. Rehhagel was not all talk. He had the successes to prove it, as he helped Werder Bremen and F.C Kaiserslautern to Bundesliga titles. This Thursday, the German football legend celebrates his 80th birthday.

A defender at heart

Rehhagel grew up in the industrial city of Essen, in the heart of the Ruhr valley of western Germany. A fierce defender, he got his start in the TuS Helene of Altenessen in 1957. Rehhagel's legacy is far-reaching as a player, but much more so as a coach.

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His most celebrated achievements were those two Bundesliga wins at Bremen in 1988 and 1993, his incredible feat of catapulting F.C Kaiserlautern from first league promotion to German champion in a single season in 1998 and coaching the winning Greek national team to victory in the 2004 UEFA European Championship.

Willi Lemke, Rehhagel's former boss at Bremen describes him as old fashioned in the best sense and a man with a footballer's heart. "Though he never studied psychology or education at a university, he is incredibly good at handling players correctly," Lemke told DW. "Certainly he was strict too, but that is part of job. He was a fantastic manager," he added.

In Bremen, Rehhagel was crowned "King Otto." Not only did he deliver those two German championships, he also led them to German Supercup trophies in 1991 and 1994, as well as the UEFA Cup Winners' Cup in 1992. Lemke was always by his side and was commonly referred to as Rehhagel's right-hand man.

'Today I am a realist'

Rehhagel could have coached anywhere he wanted. Lazio Roma, Real Madrid and even Germany's biggest beast Bayern Munich, all wanted a piece of him. In 1995, he broke the hearts of Bremen fans when he signed a contract to coach at Bayern. "I used to be an idealist. Today I am a realist and I know that, in the long run, the best football is played where the money is," Rehhagel famously said of the move.

But under his leadership, Bayern did not play its best football. The press grumbled, the Bavarian bosses considered a UEFA Cup final too little of an achievement and, for the first time, even the players had complaints. "Rehhagel or me," former Bayern midfielder Mehmet Scholl is said to have griped to the German press.

The relationship between the advice-resistant coach and the success-spoiled football club became frosty. As Bayern finished the season in second place in the Bundesliga, club President Franz Beckenbauer had enough and dismissed Rehhagel.

That is when F.C Kaiserslautern, known as the "Red Devils" came knocking. Sporting director Jürgen Friedrich was happy to bring Rehhagel to his struggling outfit. Rehhagel's dramatic transformation of the small club to German champion in 1998 was made even sweeter by the fact that Bayern Munich was in the same stadium when he and his team were crowned. "There is a football God and he sees it all," Rehhagel reflected.

Perhaps he became a type of football God himself, when he performed a miracle as coach of the Greek national team in 2004. Lemke says this feat was "Rehhagel's biggest thing." In the Euros in Portugal, Rehhagel's team of "nameless heroes" left a trail of favorites behind, pushing on with rigorous defensive football and a lot of heart to win the title.

To critics of a win that was not pretty, Rehhagel countered that "the one who wins, is the one who plays a modern game." Regardless, a sea of blue and white flags in Athens celebrated and would laud the German coach for bringing a renewed sense of honor to Greece.

A momentous reunion

"You can be incredibly happy for everything you have done, with the support of a great woman," Lemke wrote on the occasion of his friend's 80th birthday, in a reference to the coach's wife Beate Rehhagel, to whom he has been married since 1963.

Willi Lemke will be by Rehhagel's side again, as the two meet to commemorate the 25th anniversary of the German championship in Bremen this weekend.