AA 9909 then UA 5817 at Denver
Los Angeles → Denver → Durango
Timetable, Denver time
16:45AA 9909 from Los Angeles at the gate
15:50UA 5817 to Durango leaves the gate
23 h 05 apart on the timetable, overnight
UA 5817 leaves 23 h 05 after AA 9909 arrives on the timetable: more than half a day, so not a connection we count.