UA 1651 then CA 3174 at O'Hare
Denver → Chicago → Guangzhou
Timetable, Chicago time
18:38UA 1651 from Denver at the gate
17:25CA 3174 to Guangzhou leaves the gate
22 h 47 apart on the timetable, overnight
CA 3174 leaves 22 h 47 after UA 1651 arrives on the timetable: more than half a day, so not a connection we count.