AA 2771 then CZ 2502 at O'Hare
Denver → Chicago → Shanghai
Timetable, Chicago time
10:30AA 2771 from Denver at the gate
01:45CZ 2502 to Shanghai leaves the gate
15 h 15 apart on the timetable, overnight
CZ 2502 leaves 15 h 15 after AA 2771 arrives on the timetable: more than half a day, so not a connection we count.