UA 757 then WN 1749 at Denver
Seattle → Denver → Dallas
Timetable, Denver time
08:42UA 757 from Seattle at the gate
05:35WN 1749 to Dallas leaves the gate
20 h 53 apart on the timetable, overnight
WN 1749 leaves 20 h 53 after UA 757 arrives on the timetable: more than half a day, so not a connection we count.