TK 9588 then DL 977 at San Francisco
Portland (Oregon) → San Francisco → Boston
Timetable, San Francisco time
15:15TK 9588 from Portland (Oregon) at the gate
12:40DL 977 to Boston leaves the gatealso VS 2372, KE 6731, LA 7046
21 h 25 apart on the timetable, overnight
DL 977 leaves 21 h 25 after TK 9588 arrives on the timetable: more than half a day, so not a connection we count.