UA 5210 then AA 5316 at O'Hare
Saginaw → Chicago → Louisville
Timetable, Chicago time
14:15UA 5210 from Saginaw at the gate
10:11AA 5316 to Louisville leaves the gate
19 h 56 apart on the timetable, overnight
AA 5316 leaves 19 h 56 after UA 5210 arrives on the timetable: more than half a day, so not a connection we count.