AA 642 then DL 1687 at O'Hare
Dallas-Fort Worth → Chicago → Atlanta
Timetable, Chicago time
13:10AA 642 from Dallas-Fort Worth at the gate
08:04DL 1687 to Atlanta leaves the gate
18 h 54 apart on the timetable, overnight
DL 1687 leaves 18 h 54 after AA 642 arrives on the timetable: more than half a day, so not a connection we count.