"It was frustrating because the three others on the frontline scored a goal each," the Borussia Dortmund star told Japanese media on Sunday after the Samurai Blue's opening match at home in the final Asian qualifying round.
"I must fight more in the penalty area," added the 23-year-old, who did have a hand in each of the goals and registered three shots out of the team's 17.
Japan coach Alberto Zaccheroni put J.League striker Ryoichi Maeda up front with CSKA Moscow's Keisuke Honda behind him, a position usually played by Kagawa at Dortmund.
Kagawa, instead, was placed to the left of Honda with Stuttgart striker Shinji Okazaki to the right. "I'm not a player who creates chances there. I could not move in further," HE said.
Honda opened the scoring in the 12th minute and Jubilo Iwata's Maeda, a two-time J-League top scorer, doubled the account from a Kagawa pass on 51 minutes. Okazaki made it 3-0 three minutes later.
But Kagawa put his personal disappointment behind him. "It was great that we won the opening which I thought was important. I want to refocus on our next match which is coming soon," he said.
Japan, reigning Asian champions, will play Jordan in their next Group B qualifier on Friday, again in Saitama, north of Tokyo.