UA 1306 then DL 3876 at Denver
Sacramento → Denver → Austin
Timetable, Denver time
12:09UA 1306 from Sacramento at the gate
09:42DL 3876 to Austin leaves the gate
21 h 33 apart on the timetable, overnight
DL 3876 leaves 21 h 33 after UA 1306 arrives on the timetable: more than half a day, so not a connection we count.