QR 3733 then LA 5751 at Barcelona
Mahón → Barcelona → Athens
Timetable, Barcelona time
19:25QR 3733 from Mahón at the gate
17:10LA 5751 to Athens leaves the gate
21 h 45 apart on the timetable, overnight
LA 5751 leaves 21 h 45 after QR 3733 arrives on the timetable: more than half a day, so not a connection we count.