UA 5210 then AA 3436 at O'Hare
Saginaw → Chicago → Rochester (ROC)
Timetable, Chicago time
14:15UA 5210 from Saginaw at the gate
11:55AA 3436 to Rochester (ROC) leaves the gate
21 h 40 apart on the timetable, overnight
AA 3436 leaves 21 h 40 after UA 5210 arrives on the timetable: more than half a day, so not a connection we count.