Thomas Tuchel shouldered the blame as Saul Niguez suffered the ignominy of being replaced at half-time on his Chelsea debut.
'It was a hard decision but I had the feeling he struggled,' said Tuchel. 'There were some big mistakes, passing mistakes, easy ball losses which is very unusual for him. He struggled with the intensity. You could see he isn't fully adapted.
'Hopefully he can accept it was completely my responsibility. I had the feeling he could jump in and play at that level.
Saul Niguez made his Chelsea debut on Saturday evening in the 3-0 victory over Aston Villa
Thomas Tuchel substituted the star at half-time after a difficult first-half for the Spaniard
'I put him into a very difficult match after the international break and it was hard to adapt the physicality in general, and to the intensity and high pressing of Aston Villa.