1. Career
Kostas Antoniou's career spans successful periods as a player at both club and international levels, followed by administrative positions within professional football.
1.1. Club Career
Antoniou began his professional career in the late 1970s with Panathinaikos, based in his hometown of Athens. He was particularly recognized for his strong offensive abilities as a midfielder. During his tenure at Panathinaikos, he contributed to the club's success, winning four Championships in the 1983-84, 1985-86, 1989-90, and 1990-91 seasons. He also secured three Greek Cups in 1983-84, 1985-86, and 1988-89.
A notable event in his club career occurred in 1988, when Antoniou agreed to transfer to rival club Olympiacos for a sum of 24.00 M GRD. Although Antoniou had consented to the move, the president of Panathinaikos initiated legal action to prevent the transfer. The legal appeal was successful, compelling Antoniou to return to Panathinaikos. However, Antoniou publicly expressed his strong reluctance, stating in an interview, "I'm not going to return to Panathinaikos - not even dead," a sentiment also captured as "I will not return to Panathinaikos, even if I have to bite the dust." As a result of this dispute and his refusal, Antoniou spent approximately six months unable to play, effectively sidelined from competitive football, before he was permitted to resume his playing career. In the winter of 1994, he moved to Athinaikos, where he ultimately concluded his playing career.
1.2. International Career
Kostas Antoniou was a significant member of the Greece national football team, making his debut in 1984. Throughout his international career, which lasted until 1993, he accumulated a total of 35 appearances for Greece. During these matches, Antoniou scored 3 goals, contributing to his national team's efforts on the international stage.
1.3. Post-playing Career
Following his retirement as a professional footballer, Kostas Antoniou transitioned into administrative roles within the sport. In May 2008, he returned to his former club, Panathinaikos, this time in an administrative capacity. He served in key positions such as Director of Football and Technical Advisor. His tenure in these roles continued until June 2010. His departure from Panathinaikos coincided with the resignation of the club's president, Nicolas Pateras, with Antoniou also stepping down from his administrative duties at that time.
2. Honours
Kostas Antoniou achieved significant success during his playing career, particularly with Panathinaikos.
- Alpha Ethniki (Championships):
- 1983-84
- 1985-86
- 1989-90
- 1990-91
- Greek Cup:
- 1983-84
- 1985-86
- 1987-88
- 1988-89
- 1990-91
- 1992-93
- 1993-94
- Greek Super Cup:
- 1988
- 1993