WN 4580 then WN 1749 at Denver
Tucson → Denver → Dallas
Timetable, Denver time
09:45WN 4580 from Tucson at the gate
05:35WN 1749 to Dallas leaves the gate
19 h 50 apart on the timetable, overnight
WN 1749 leaves 19 h 50 after WN 4580 arrives on the timetable: more than half a day, so not a connection we count.