FR 6973 then OS 552 at Fiumicino
Barcelona → Rome → Vienna
Timetable, Rome time
12:30FR 6973 from Barcelona at the gate
10:15OS 552 to Vienna leaves the gate
21 h 45 apart on the timetable, overnight
OS 552 leaves 21 h 45 after FR 6973 arrives on the timetable: more than half a day, so not a connection we count.