UA 4774 then AA 529 at O'Hare
Tucson → Chicago → Knoxville
Timetable, Chicago time
13:02UA 4774 from Tucson at the gate
10:36AA 529 to Knoxville leaves the gate
21 h 34 apart on the timetable, overnight
AA 529 leaves 21 h 34 after UA 4774 arrives on the timetable: more than half a day, so not a connection we count.