AA 537 then F9 1051 at DFW
St Louis → Dallas-Fort Worth → Las Vegas
Timetable, Dallas-Fort Worth time
08:35AA 537 from St Louis at the gate
08:30F9 1051 to Las Vegas leaves the gate
23 h 55 apart on the timetable, overnight
F9 1051 leaves 23 h 55 after AA 537 arrives on the timetable: more than half a day, so not a connection we count.