UA 2265 then QF 3748 at San Francisco
Denver → San Francisco → San Diego
Timetable, San Francisco time
07:49UA 2265 from Denver at the gatealso AC 3333
20:00QF 3748 to San Diego leaves the gate
12 h 11 apart on the timetable
QF 3748 leaves 12 h 11 after UA 2265 arrives on the timetable: more than half a day, so not a connection we count.