AA 4504 then UA 8157 at O'Hare
South Bend → Chicago → Tampa
Timetable, Chicago time
18:35AA 4504 from South Bend at the gate
13:55UA 8157 to Tampa leaves the gate
19 h 20 apart on the timetable, overnight
UA 8157 leaves 19 h 20 after AA 4504 arrives on the timetable: more than half a day, so not a connection we count.