UA 3913 then UA 697 at Houston
Denver → Houston → San Antonio
Timetable, Houston time
21:22UA 3913 from Denver at the gate
14:30UA 697 to San Antonio leaves the gate
17 h 08 apart on the timetable, overnight
UA 697 leaves 17 h 08 after UA 3913 arrives on the timetable: more than half a day, so not a connection we count.