AA 9866 then ET 3511 at O'Hare
Marquette → Chicago → Muscat
Timetable, Chicago time
10:30AA 9866 from Marquette at the gate
09:05ET 3511 to Muscat leaves the gate
22 h 35 apart on the timetable, overnight
ET 3511 leaves 22 h 35 after AA 9866 arrives on the timetable: more than half a day, so not a connection we count.