UA 3902 then AA 1968 at O'Hare
Rio De Janeiro → Chicago → Tucson
Timetable, Chicago time
17:01UA 3902 from Rio De Janeiro at the gate
11:40AA 1968 to Tucson leaves the gate
18 h 39 apart on the timetable, overnight
AA 1968 leaves 18 h 39 after UA 3902 arrives on the timetable: more than half a day, so not a connection we count.