AA 4504 then UA 5693 at O'Hare
South Bend → Chicago → Knoxville
Timetable, Chicago time
18:35AA 4504 from South Bend at the gate
14:07UA 5693 to Knoxville leaves the gate
19 h 32 apart on the timetable, overnight
UA 5693 leaves 19 h 32 after AA 4504 arrives on the timetable: more than half a day, so not a connection we count.