Manchester United fullback Alexander Buttner admits he let himself down during their Champions League win over Braga.
Buttner was at fault for one of Braga's goals.
"Of course, it's stupid if your direct opponent scores,'' said Buttner.
"But it did not hurt my confidence. It is natural to take time to get used to a completely different level. But it went well.
"This is a fantastic club, the people are nice and you train with very good players. I'm going to step forward.''