WN 4626 then UA 489 at Denver
Nashville → Denver → Houston
Timetable, Denver time
18:00WN 4626 from Nashville at the gate
15:35UA 489 to Houston leaves the gate
21 h 35 apart on the timetable, overnight
UA 489 leaves 21 h 35 after WN 4626 arrives on the timetable: more than half a day, so not a connection we count.