F9 1323 then UA 617 at Denver
Dallas-Fort Worth → Denver → Chicago O'Hare
Timetable, Denver time
14:04F9 1323 from Dallas-Fort Worth at the gate
13:25UA 617 to Chicago O'Hare leaves the gate
23 h 21 apart on the timetable, overnight
UA 617 leaves 23 h 21 after F9 1323 arrives on the timetable: more than half a day, so not a connection we count.