"Quite simply I am relieved. But being a member of the team is not my goal. My aim is to deliver results."
Despite his concerns, the 25-year-old is a certain starter for Japan's campaign in Brazil even though he has been deemed surplus to requirements during the English Premier League season under former United boss David Moyes, who was sacked last month.
It marked an abrupt change in fortunes for the talented playmaker, who had two impressive years with German side Borussia Dortmund before being signed by former United boss Alex Ferguson in 2012.
"I have experienced a lot in Europe over these four years, especially this year. I had won the league the previous three years," he said.
"This year the manager changed and it has been a really hard year in many ways but I think it has been really good for me to experience both good times and bad times at the top level in Europe.
"There have been times when I thought my spirit would break and I just thought I have to believe in myself. In the end it has been a really disappointing season what with not scoring a single goal but I was never slacked off in training or matches."
GETTING RESULTS
Kagawa was one of a number of young players who travelled with the Japan squad at the last World Cup in South Africa for experience after missing out on the 23-man party.
Frustrated at being overlooked by former Japan coach Takeshi Okada, Kagawa completed the shock move from then second division side Cerezo Osaka to Dortmund where he helped sparked their Bundesliga revival.
Although he has failed to hit the same heights at Old Traforrd, Kagawa has continued to shine under Zaccheroni and he looked forward to taking on Ivory Coast, Colombia and Greece in their Group C campaign with relish.
"Over these past four years my goal has been Brazil and I think I am here now because I fought and believed in myself," he said.
"I can play on a World Cup stage that I have dreamed about since I was little. I am not only going to enjoy it, I want to attach my mind to getting results.
"For the team I think our first game against Ivory Coast is crucial. Obviously we are in it to win the tournament but that is not something you can say lightly and I want to focus on Ivory Coast."
(Writing by Patrick Johnston; Editing by John O'Brien)
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