GQ 311 then A3 780 at Athens
Samos → Athens → Zagreb
Timetable, Athens time
15:40GQ 311 from Samos at the gate
13:20A3 780 to Zagreb leaves the gate
21 h 40 apart on the timetable, overnight
A3 780 leaves 21 h 40 after GQ 311 arrives on the timetable: more than half a day, so not a connection we count.