DL 775 then UA 609 at Atlanta
Cleveland → Atlanta → Denver
Timetable, Atlanta time
17:06DL 775 from Cleveland at the gate
16:39UA 609 to Denver leaves the gate
23 h 33 apart on the timetable, overnight
UA 609 leaves 23 h 33 after DL 775 arrives on the timetable: more than half a day, so not a connection we count.