UA 5935 then DL 840 at Denver
Salt Lake City → Denver → Atlanta
Timetable, Denver time
20:03UA 5935 from Salt Lake City at the gate
17:07DL 840 to Atlanta leaves the gate
21 h 04 apart on the timetable, overnight
DL 840 leaves 21 h 04 after UA 5935 arrives on the timetable: more than half a day, so not a connection we count.