UA 751 then UA 1031 at San Francisco
Portland (Oregon) → San Francisco → Houston
Timetable, San Francisco time
15:15UA 751 from Portland (Oregon) at the gatealso CM 1419, AC 3338, VA 8585, NZ 9358
14:30UA 1031 to Houston leaves the gatealso EK 6418, NH 7336, CA 7344, VA 8083, NZ 9196
23 h 15 apart on the timetable, overnight
UA 1031 leaves 23 h 15 after UA 751 arrives on the timetable: more than half a day, so not a connection we count.