[1] Markopoulos began playing the sport of basketball with the youth system of Iraklis Thessaloniki, in Greece.

[5][6] With Iraklis' Under-18 junior club, along with his teammate Lazaros Papadopoulos, Markopoulos won the Greek Under-18 Championship, during the 1997–98 season.

After that, Markopoulos was recruited to play college basketball in the NCAA Division I, by the University of North Carolina.

At age 19, due to the illness, Markopoulos became paralyzed, during a flight from Thessaloniki to Luleå, on 7 February 2001.

At the age of 23, he retired from playing professional basketball, after competing with Xanthi, in the Greek 2nd Division, during the 2004–05 season.