Anastasiadis began his career at Heidelberg United before being signed by the Greek club PAOK Thessaloniki FC at the age of 19.
[1] He made his debut in 1988 and became an influential part of the team, playing in 18 Alpha Ethniki matches, 5 cup games and 24 friendlies in the 1988/89 season, scoring 12 goals in total.
In 2005, with the return of South Melbourne to the Victorian Premier League after the disbandment of the NSL competition, Anastasiadis put his hand up for the job which few wanted.
Despite taking charge of a young squad which had been destroyed by the FFA and was quickly assembled merely weeks before the start of the new season, and which was labelled as a relegation candidate at the start of the year, Anastasiadis led the side to 3rd place on the ladder at the end of the season and as far as the Preliminary Final, where the team lost 1–0 to Heidelberg United and was knocked out.
Since the move to Bentleigh, John has seen his team reach the VPL grand final in 2013, the semi-final of the inaugural FFA Cup in 2014 and win the club's first ever major title when Bentleigh beat South Melbourne FC at Lakeside Stadium in the National Premier Leagues Victoria Grand Final.
Anastasiadis continued the success with Bentleigh winning the FFV Community Shield, beating foes South Melbourne FC at Kingston Heath Soccer Complex 3–0,[3] the 2016 Dockerty Cup, the second major trophy in its history and first Dockerty Cup title, with a 1–0 victory over Green Gully SC,[4] and just four days later, picked up the third piece of silverware for 2016, winning the NPL Victoria minor premiership for the first time in the club's history.