Career
He played 110 games in the now-defunct National Soccer League scoring 4 goals with South Melbourne, Adelaide City and Adelaide United. In mid-2007 Valkanis was named captain of his club side, Adelaide United, replacing Angelo Costanzo (who had been appointed as interim captain after the resignation and departure of Ross Aloisi). Valkanis announced his intention to retire at the end of the 2008-2009 A-League season in December 2008.
Valkanis" international debut was for the Socceroos in an Asian Cup qualifier versus Kuwait at Aussie Stadium on 16 August 2006.
After the resignation of Adelaide United manager John Kosmina on 28 January 2013, Valkanis was appointed caretaker manager of Adelaide United for the remainder of the A-League season. Under Valkanis, Adelaide United managed to finish the A-League season in 4th place, therefore qualifying for the A-League finals.
However, they were eliminated in the first round by Brisbane Roar. Valkanis is of Greek descent.
He attended De Louisiana Salle College, Malvern.