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.
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.
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.