FR 6921 then LA 5751 at Barcelona
Dublin → Barcelona → Athens
Timetable, Barcelona time
21:40FR 6921 from Dublin at the gate
17:10LA 5751 to Athens leaves the gate
19 h 30 apart on the timetable, overnight
LA 5751 leaves 19 h 30 after FR 6921 arrives on the timetable: more than half a day, so not a connection we count.