LA 6139 then MS 9323 at San Francisco
Boston → San Francisco → Washington
Timetable, San Francisco time
23:58LA 6139 from Boston at the gate
22:55MS 9323 to Washington leaves the gate
22 h 57 apart on the timetable, overnight
MS 9323 leaves 22 h 57 after LA 6139 arrives on the timetable: more than half a day, so not a connection we count.