AA 9909 then UA 2424 at Denver
Los Angeles → Denver → Las Vegas
Timetable, Denver time
16:45AA 9909 from Los Angeles at the gate
16:13UA 2424 to Las Vegas leaves the gate
23 h 28 apart on the timetable, overnight
UA 2424 leaves 23 h 28 after AA 9909 arrives on the timetable: more than half a day, so not a connection we count.