F9 1230 then WN 1749 at Denver
San Francisco → Denver → Dallas
Timetable, Denver time
09:40F9 1230 from San Francisco at the gate
05:35WN 1749 to Dallas leaves the gate
19 h 55 apart on the timetable, overnight
WN 1749 leaves 19 h 55 after F9 1230 arrives on the timetable: more than half a day, so not a connection we count.