UA 3884 then AA 3323 at O'Hare
Melbourne (Florida) → Chicago → Las Vegas
Timetable, Chicago time
01:06UA 3884 from Melbourne (Florida) at the gate
20:53AA 3323 to Las Vegas leaves the gate
19 h 47 apart on the timetable
AA 3323 leaves 19 h 47 after UA 3884 arrives on the timetable: more than half a day, so not a connection we count.