|Date of birth||10 February 1991|
|Place of birth||Athens, Greece|
|Height||1.89 m (6 ft 2 in)|
|Playing position||Center back / Defensive midfielder|
* Senior club appearances and goals counted for the domestic league only and correct as of 25 August 2015.
Koutroubis could not be officially announced by Panathinaikos, because he still had a contract with AEK Athens. On June 26, 2013, he participated in Panathinaikos first training session for the 2013-2014 season. On July 2, 2013, he filed an appeal against AEK Athens, in order to get whatever the team owed to him. On the same day, he travelled to the Netherlands and Osterberg, in order to take part in Panathinaikos' summer preparation. On 17 July 2013, it was officially announced that Koutroubis had signed a four-years contract with Panathinaikos.
As of 8 February 2015[update]