F9 4567 then UA 5263 at Denver
St Louis → Denver → Dallas-Fort Worth
Timetable, Denver time
21:30F9 4567 from St Louis at the gate
20:45UA 5263 to Dallas-Fort Worth leaves the gate
23 h 15 apart on the timetable, overnight
UA 5263 leaves 23 h 15 after F9 4567 arrives on the timetable: more than half a day, so not a connection we count.