AA 644 then UA 2085 at Phoenix
Tampa → Phoenix → Denver
Timetable, Phoenix time
20:50AA 644 from Tampa at the gate
16:31UA 2085 to Denver leaves the gate
19 h 41 apart on the timetable, overnight
UA 2085 leaves 19 h 41 after AA 644 arrives on the timetable: more than half a day, so not a connection we count.