AA 3854 then UA 4772 at O'Hare
Rochester (RST) → Chicago → Columbia Regional
Timetable, Chicago time
17:59AA 3854 from Rochester (RST) at the gate
12:45UA 4772 to Columbia Regional leaves the gate
18 h 46 apart on the timetable, overnight
UA 4772 leaves 18 h 46 after AA 3854 arrives on the timetable: more than half a day, so not a connection we count.