F9 1748 then DL 3876 at Denver
Phoenix Sky Harbor → Denver → Austin
Timetable, Denver time
11:59F9 1748 from Phoenix Sky Harbor at the gate
09:42DL 3876 to Austin leaves the gate
21 h 43 apart on the timetable, overnight
DL 3876 leaves 21 h 43 after F9 1748 arrives on the timetable: more than half a day, so not a connection we count.