UA 3913 then UA 1192 at Houston
Denver → Houston → San Juan
Timetable, Houston time
21:22UA 3913 from Denver at the gate
10:13UA 1192 to San Juan leaves the gate
12 h 51 apart on the timetable, overnight
UA 1192 leaves 12 h 51 after UA 3913 arrives on the timetable: more than half a day, so not a connection we count.