Jurgen Klopp's rise from Bundesliga 2. to one of the most-wanted managers

Picking Klopp was seen as a huge risk. He hadn't won any serious trophy, neither as coach nor player; he was still a nobody. 'He was reluctant to do it at first but he agreed because he wanted to be able to see the World Cup games a year later, up close and get tickets,' says Doehling. Klopp proved an immediate, huge success, cutting his teeth on a new video tool that allowed him to draw circles and arrows on to the screen. 'It was his idea,' says Doehling. 'He basically developed the tool in cooperation with the software company we employed because he wanted to use it for his team talks at Mainz after the World Cup.'

Klopp was able to illuminate tactical details on screen 'in an entertaining, funny, sexy manner', Doehling says. Crucially, he employed self-deprecating humour to avoid patronising the audience. He spoke to them as a friend in a pub might, without airs and graces; not down to them, in headmasterly fashion. He was a revelation. 'We realised that this guy knew how to put his point across and to mesmerise people,' says Doehling. 'If he had started a political party, they would have voted him into government immediately.'

The Mainz coach resumed his pundit's role at the 2006 World Cup, where he'd occasionally be flanked by Pelé as well as Beckenbauer. The latter frequently nodded in agreement with Klopp's snippets of insights, such as identifying the problem with a full-back's position or a defender reacting too slowly to a goal-kick from the opposition. Doehling: 'Beckenbauer's approval was like getting knighted for Klopp. If the Kaiser thought he knew his stuff - he really knew his stuff.'

ZDF's coverage of the tournament in front of a partying crowd at Berlin's Sony Centre was a huge success. Doehling modestly says Germany's performances, five weeks of sunshine and the festive mood in the whole country created a wave of goodwill that swept the show along but the award-winning programme genuinely broke new ground thanks to Klopp's input.

'He contributed something that didn't exist before his debut at the Confederations Cup: he simply talked about what was happening on the pitch,' wrote Christoph Biermann, one of the first German football journalists to cover tactics extensively, in Süddeutsche Zeitung. Gone was the armchair psychology, the obsession with character, the will to fight and other invisible factors that were impossible to prove one way or the other. In came attention to the little, easily fixable things that cumulatively made all the difference.

Other Bundesliga coaches should thank Klopp 'for introducing a bit more objectivity into the way football is being talked about', Biermann noted, 'but he is perhaps also lucky that he can continue to explain football relatively unhindered these days while his colleague Ralf Rangnick took years to atone for the impudence of explaining the back four.' Times had changed, at last. By enabling average audiences of twenty-five million people to view football differently, Klopp had a hand in football being viewed differently as well.

Doehling is reluctant to ascribe too much influence to the ZDF World Cup coverage and the matey, good-natured moments of enlightenment offered by Klopp. 'The first, big, heavy stone that was thrown at the glass window came from Klinsmann. He kicked open the doors and decreed that there shouldn't be any more doors in that place from now on, to let some air in. He was the locomotive, the trailblazer. Everyone else just followed in his slipstream.' But, Doehling says, giving Klopp the platform to become something like the 'Fernseh-Bundestrainer', the TV national manager, invariably gave legitimacy to Klopp's idiosyncratic footballing blueprint, too. The coach also used his time at the big tournaments to watch other teams and learn the machinations of television. 'At first he was shy,' recalls Doehling, 'but after a short time he was effectively coaching our whole team.'

Klopp continued his work at the channel until the end of Euro 2008. By that time (2006-7), Mainz had been relegated back down to Bundesliga 2 and Klopp had resigned on the last day of the next season, after 05 had narrowly missed out on promotion. Twenty thousand supporters turned out at his farewell party in the city centre that night. Klopp, overcome with emotion, told them: 'You have made me everything I am, everything I can do.'

Doehling remembers working with Klopp at the DFB Cup final between Bayern and Dortmund in April of that year. 'He said to me, "Jan, I want to be down there on the touchline one day." ' Back at their Berlin hotel, Dortmund fans were serenading him with 'Jürgen Klopp, you are the best man' in the lobby. They wanted him to take over their club the next season. Leverkusen and Hamburg put feelers out, too. The latter turned him down after a scouting report had highlighted his penchant for jeans with holes and an alleged habit of turning up late for training. Even Bayern's general manager Uli Hoeness had taken a shine to Klopp, but the Bavarian giants employed Jürgen Klinsmann to bring modernity to Säbener Strasse instead. The former Germany manager was considered a safer pair of hands, probably because of his extensive experience of playing at the top level.