UA 5276 then WN 581 at Denver
Tulsa → Denver → Nashville
Timetable, Denver time
12:45UA 5276 from Tulsa at the gate
07:55WN 581 to Nashville leaves the gate
19 h 10 apart on the timetable, overnight
WN 581 leaves 19 h 10 after UA 5276 arrives on the timetable: more than half a day, so not a connection we count.