Club Stamatiadis started playing football in 1947 at AE Melandias. In 1950, at the age of 15, he signed a sport's card for Sparta Petralona, but a mistake in the signing of the card by the secretary of the club, essentially canceled his card. Then his father, Dimitris with the then manager of Sparta Petralona,
Mimis Seltsikas, took him for a trial to the
academy of
AEK Athens at
Nea Filadelfeia. Stamatiadis who was encouraged by his father and was a supporter of the yellow-blacks, eventually became a member of their academies. The experienced manager of the men's team,
Jack Beby, immediately recognized his potential and with appropriate advice and guidance helped his development and establishment as a left winger, where he flourished during the rich of his career acquiring the nickname "the Arrow" (''''). Beby's successor,
Mario Magnozzi, gave him the opportunity to play for the first time in 1952 in a derby against
Olympiacos. Thus, Stamatiadis managed to compete in two matches alongside his childhood idol,
Kleanthis Maropoulos, before the latter, retired as a footballer. For the following 15 years, he became one of the main players of the yellow-blacks, taking over the captaincy of the team from
Giannis Kanakis and until the moment he passed it to
Mimis Papaioannou, becoming the longest serving captain of AEK. Proof of his leadership skills was the respect he enjoyed from his teammates from time to time, as well as the trust shown in his person by the respective administrations and managers for his composure, equanimity and rationality. As a captain, he won 2
championships, as well as the
Greek Cup in 1966, while the Cup in 1956 was also to his achievements. He was a regular of the Athens Mixed Team selections during the 1950s. On 3 December 1967 in a 4–1 away victory over Olympiacos, his ultimately fruitless attempt to "admonish" in the middle of the match the young and hyperbole
Spyros Pomonis, in order to simplify his way of playing for AEK to reach an even wider dominance, instead of his insistence on ridiculing the personal opponent, Orestis Pavlidis. Pomonis eventually insisted on humiliating his opponent and AEK missed the opportunity for a wider score against the red and whites and Pavlidis took the decision that the role of referee suited him better, by retiring as a footballer. He was one of the main players of the team that won second place in the
Balkans Cup in
1967, losing only in the final by
Fenerbahçe. In his last season with the club, they reached the
quarter-finals of the
European Cup. On 18 May 1969, he played for the last time in the 2–1 victory over
Veria, where AEK won a penalty and was awarded to him by his teammates. Stamatis, charged by the emotions of the moment missed the penalty. In the summer of 1969, in the context of a general renewal of the club's roster by the manager
Branko Stanković, he decided to retire at the age of 34, due to his intention to not compete for any other club.
International Stamatiadis had a total of eight appearances with
Greece. He made his debut at the age of 19, on 8 March 1954 in a 2–0 away victory over
Israel in the
1954 FIFA World Cup qualifiers. His last appearance was on 27 November 1963 against
Cyprus in an away friendly match. ==Managerial career==