The 23-year-old completed his transfer in June for an undisclosed fee on a four-year deal following months of speculation linking him with a move to the Red Devils.
Kagawa scored 17 goals in 40 appearances for Dortmund last term as Jürgen Klopp’s side won the Bundesliga title for the second successive year and eased to a 5-2 victory over Bayern Munich in the German Cup final.
The Japan international has already scored once in pre-season but is keen to prove his talent and create more goals for the 19-time English champions.
“Every time I practice with my team-mates it’s satisfying,” said Kagawa. “When I get used to my new surrounding more, I’ll do even better.
“I know most of the time I could do better and bring out my strong points. I feel as if I should be making more chances to get goals.”
Kagawa also believes having talents such as Nani and Wayne Rooney in the United first-team will help him produce his best form for the Red Devils.
“Having reliable players on both sides of me makes things easier,” he added. “I can play in one or two positions, and if I play well in them and get hold of the ball, I’ll be able to create goals.
“I’ll keep trying for good form so my team-mates can trust me and my presence in the team.”
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