EC 7154 then IB 5096 at Barcelona
Milan → Barcelona → Porto
Timetable, Barcelona time
23:15EC 7154 from Milan at the gate
20:25IB 5096 to Porto leaves the gate
21 h 10 apart on the timetable, overnight
IB 5096 leaves 21 h 10 after EC 7154 arrives on the timetable: more than half a day, so not a connection we count.