FR 6927 then FR 7815 at Fiumicino
Barcelona → Rome → Thessaloniki
Timetable, Rome time
15:00FR 6927 from Barcelona at the gate
06:10FR 7815 to Thessaloniki leaves the gate
15 h 10 apart on the timetable, overnight
FR 7815 leaves 15 h 10 after FR 6927 arrives on the timetable: more than half a day, so not a connection we count.