AA 9928 then UA 2148 at O'Hare
New York LaGuardia → Chicago → Denver
Timetable, Chicago time
06:45AA 9928 from New York LaGuardia at the gate
21:00UA 2148 to Denver leaves the gate
14 h 15 apart on the timetable
UA 2148 leaves 14 h 15 after AA 9928 arrives on the timetable: more than half a day, so not a connection we count.