DL 9979 then DL 1946 at Atlanta
Detroit → Atlanta → San Juan
Timetable, Atlanta time
15:41DL 9979 from Detroit at the gate
13:15DL 1946 to San Juan leaves the gate
21 h 34 apart on the timetable, overnight
DL 1946 leaves 21 h 34 after DL 9979 arrives on the timetable: more than half a day, so not a connection we count.