The Armenian improved in the second-half of the season and finished the season strongly, scoring in the 2-0 Europa League final victory over Ajax Amsterdam.
"For sure I will be a better player for this experience," Mkhitaryan told reporters.
"Last year with my difficulties they helped me a lot. I could stay more strong in my mind, like mentally,"
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"It shows that you are strong enough to win them over or not. I think I have done everything to work hard, to show everyone I can play and that I can do my best for the team."
Mkhitaryan said United have set higher targets ahead of the upcoming season after finishing with League Cup and Europa League title in Mourinho's first season at Old Trafford.
"The manager in general is saying that we need to do more," the 28-year-old added.
"We know this season is going to be a little bit harder because we are not going to play in the Europa League we are going to play in the Champions League, which is different."
United, who finished sixth in the league last season, host West Ham United on Aug. 13 in the opening game of their campaign on Aug. 13.
(Reporting by Hardik Vyas in Bengaluru; editing by Amlan Chakraborty)
