UA 3532 then AA 3890 at O'Hare
Knoxville → Chicago → Sioux Falls
Timetable, Chicago time
18:43UA 3532 from Knoxville at the gate
12:26AA 3890 to Sioux Falls leaves the gate
17 h 43 apart on the timetable, overnight
AA 3890 leaves 17 h 43 after UA 3532 arrives on the timetable: more than half a day, so not a connection we count.