UA 1970 then UA 2803 at San Francisco
Cleveland → San Francisco → Denver
Timetable, San Francisco time
21:45UA 1970 from Cleveland at the gatealso VA 8489, NZ 9046, OZ 9526
13:00UA 2803 to Denver leaves the gatealso AC 4049, CA 7309, NH 7310, VA 8338, NZ 9056
15 h 15 apart on the timetable, overnight
UA 2803 leaves 15 h 15 after UA 1970 arrives on the timetable: more than half a day, so not a connection we count.