AA 642 then UA 2145 at O'Hare
Dallas-Fort Worth → Chicago → Sacramento
Timetable, Chicago time
13:10AA 642 from Dallas-Fort Worth at the gate
09:11UA 2145 to Sacramento leaves the gate
20 h 01 apart on the timetable, overnight
UA 2145 leaves 20 h 01 after AA 642 arrives on the timetable: more than half a day, so not a connection we count.