The Japan international is putting pressure on Rooney, but Hansen isn't so sure.
He wrote in the Telegraph: "He (Sir Alex Ferguson) has now started to talk up the performances of Shinji Kagawa, explaining that the Japanese midfielder's performance at West Ham last Wednesday resulted in him substituting Rooney.
"For all Kagawa's talent and ability, he is no Wayne Rooney, and the likes of Chelsea, Arsenal and Manchester City would much rather face a United team with Kagawa in it than Rooney. Kagawa has done OK in his first season in the Premier League since arriving from Borussia Dortmund, but away from home and in bad conditions, if he is struggling you will not see him.
"You would take Rooney ahead of him every time because, even in a season when he has struggled for form and rarely played as an out-and-out striker, he has scored 16 goals in 34 games, which is not a bad return at all."