After that, he played with the Greek club Olympiacos Piraeus, from 1990 to 1994.

He played with the Greek club Panionios Athens, during the 1994–95 season.

Karatzas was a member of the senio Greek national team.

He played with Greece at the 1986 FIBA World Championship.

He was also a member of the Greek team that won the gold medal at the 1987 FIBA EuroBasket.