Mourinho started the French midfielder in Friday night’s Premier League opener after just a few days’ training.
Pogba scored from the penalty spot to give United the lead in the first half with Luke adding the second goal late in the second half.
Pogba had his first training session on Monday but impressed to such an extent with his application and physical condition that he was picked to start.
The Portuguese coach handed Pogba the captaincy.
Asked about the significance of making Pogba captain, Mourinho told Sky Sportsm, “Last season, he was captain a few times.
“Valencia is captain, but Valencia is not here.
“Paul is one of the options, third season, made in the academy, understands the club, the culture, good relationship with his teammates and a good example today putting himself in the team.”