FR 4584 then SN 3698 at Barcelona
Porto → Barcelona → Brussels
Timetable, Barcelona time
18:35FR 4584 from Porto at the gate
12:25SN 3698 to Brussels leaves the gate
17 h 50 apart on the timetable, overnight
SN 3698 leaves 17 h 50 after FR 4584 arrives on the timetable: more than half a day, so not a connection we count.