AA 4504 then UA 5751 at O'Hare
South Bend → Chicago → Columbus (Ohio)
Timetable, Chicago time
18:35AA 4504 from South Bend at the gate
14:16UA 5751 to Columbus (Ohio) leaves the gate
19 h 41 apart on the timetable, overnight
UA 5751 leaves 19 h 41 after AA 4504 arrives on the timetable: more than half a day, so not a connection we count.