The former Australia boss, in his second season in Japan, guided Yokohama F. Marinos to their first J. League title in 15 years, despite a limited transfer budget. In doing so he became the first Australian manager to win a league title in Japan.
He also led Brisbane Roar to back to back A-League championships, a premiership and consecutive qualification to the AFC Champions League, as well as being the record holder of the longest undefeated streak in Australian sporting history; 36 games in 2011/12.
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As a former Socceroos manager, Postecoglou guided the country to the AFC Asian Cup in 2015 and then twice led his team to the World Cup, in 2014 and 2018; a manager with a clear plan, a specific philosophy based on a passing game with relentless pressing, an attacking approach and based on creating a machine without superstars.
Postecoglou, a low profile coach with self-confidence, although he was ignored by Greek clubs – he was born in Athens and emigrated to Australia at the age of five – and was not considered an option by the Greek FA, even though he was willing to accept a low salary to coach the Greece national team, is now set to write history in Scotland at Celtic.
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Last year Inside Futbol asked Postecoglou about the next chapter of his career and his ambition to try his luck in Europe.
“I have moved to a level in my career where I don’t have to prove what I can do”, he told us.
“I believe that something will happen in Europe and that when the right time comes I will succeed there as well, making the right process, however it is not something I am chasing right now.
“My philosophy in these things is always to do the job I have as best I can and to leave my mark, which will mean not only have I succeeded, but also that people who attend the club’s games will remember what we have achieved.”
Postecoglou faces a rebuilding job at Celtic as the Bhoys try to make sure Rangers winning the Scottish Premiership last season was just a blip.
It remains to be seen if the Australian can do the job, but he arrives underrated and confident his time to succeed in European football has come.