BT 5168 then IB 409 at Madrid
Brussels → Madrid → Barcelona
Timetable, Madrid time
14:40BT 5168 from Brussels at the gatealso AY 5625, AA 8515
10:25IB 409 to Barcelona leaves the gatealso LA 1624, CX 1827, LL 3009, VY 5116, AV 6078, BA 7129, QR 7246, AA 8727
19 h 45 apart on the timetable, overnight
IB 409 leaves 19 h 45 after BT 5168 arrives on the timetable: more than half a day, so not a connection we count.