AA 1494 then UA 3876 at O'Hare
San Diego → Chicago → Miami
Timetable, Chicago time
04:49AA 1494 from San Diego at the gate
21:00UA 3876 to Miami leaves the gate
16 h 11 apart on the timetable
UA 3876 leaves 16 h 11 after AA 1494 arrives on the timetable: more than half a day, so not a connection we count.