Borussia Dortmund's Shinji Kagawa believes his current slump in form will make him a better player.
The Japan midfielder enjoyed a sensational debut season in the Bundesliga last term but is currently in a dip in form which saw him kept on the bench for the first time in Dortmund's recent 4-0 win over Augsburg.
But the 22-year-old retains confidence in his ability and is sure he will recapture his best form.
He told Kyodo News: "I'm suffering because I am not delivering results.
"It's easy to play with joy when everything is going well. It's a mental problem that I have at this moment. In order to be a better player this is what I have to go through.
"Last season I was able to find confidence and this confidence I have will not go away that easily. I am suffering now but I know that is going to change.
"This is what I need for me to grow as a player and at this point just scoring one goal won't change anything.
"I know that not everything is easy. I think this is the most difficult point in my football career but I will definitely get through it."