UA 3532 then AA 6346 at O'Hare
Knoxville → Chicago → Lexington
Timetable, Chicago time
18:43UA 3532 from Knoxville at the gate
15:45AA 6346 to Lexington leaves the gate
21 h 02 apart on the timetable, overnight
AA 6346 leaves 21 h 02 after UA 3532 arrives on the timetable: more than half a day, so not a connection we count.