The hosts trailed 2-1 at halftime as Maris Verpakovskis netted twice following a fourth-minute opener from Gekas, but the 2004 European champions rallied to romp home.
And goalkeeper Jung Sung-ryong was forced into his first genuine save of the match when he parried Theofanis Gekas's stinging shot on the turn from the edge of the box over the bar for a corner in the 81st minute.