BR 658 then UA 1810 at Toronto Pearson
Chicago O'Hare → Toronto → Denver
Timetable, Toronto time
16:35BR 658 from Chicago O'Hare at the gate
16:10UA 1810 to Denver leaves the gate
23 h 35 apart on the timetable, overnight
UA 1810 leaves 23 h 35 after BR 658 arrives on the timetable: more than half a day, so not a connection we count.