AA 4504 then UA 2142 at O'Hare
South Bend → Chicago → Nashville
Timetable, Chicago time
18:35AA 4504 from South Bend at the gate
14:05UA 2142 to Nashville leaves the gate
19 h 30 apart on the timetable, overnight
UA 2142 leaves 19 h 30 after AA 4504 arrives on the timetable: more than half a day, so not a connection we count.