FR 270 then LA 5788 at Barcelona
Milan → Barcelona → Santander
Timetable, Barcelona time
17:45FR 270 from Milan at the gate
16:05LA 5788 to Santander leaves the gate
22 h 20 apart on the timetable, overnight
LA 5788 leaves 22 h 20 after FR 270 arrives on the timetable: more than half a day, so not a connection we count.