FR 3977 then LA 5751 at Barcelona
Dublin → Barcelona → Athens
Timetable, Barcelona time
21:10FR 3977 from Dublin at the gate
17:10LA 5751 to Athens leaves the gate
20 h apart on the timetable, overnight
LA 5751 leaves 20 h after FR 3977 arrives on the timetable: more than half a day, so not a connection we count.