FR 2540 then AM 20 at Madrid
Bucharest → Madrid → Mexico City
Timetable, Madrid time
13:55FR 2540 from Bucharest at the gate
13:30AM 20 to Mexico City leaves the gate
23 h 35 apart on the timetable, overnight
AM 20 leaves 23 h 35 after FR 2540 arrives on the timetable: more than half a day, so not a connection we count.