Chelsea manager Thomas Tuchel said Saul Niguez made “big mistakes” in his debut on Saturday against Aston Villa.
The German tactician picked his line-up thinking the midfielder would be able to adapt right away to the pace of play before replacing the Spain international at half-time of a 3-0 win.
Saul, on loan from Atletico Madrid, did not train in pre-season with the Blues as he arrived just before the transfer deadline.
“I had the feeling that he struggled,” Tuchel told Sky Sports. “There were some big mistakes, passing mistakes, and he struggled with the intensity. You could see he isn’t fully adapted.
“It’s completely my responsibility. I had the feeling he could jump in for us and play at that level. I [then] thought it was maybe better to change him, but it doesn’t change anything [about how I see him].”
The head coach later added: “It’s very hard. You can either do it or not do it. I told him before it was my responsibility if it does not work out for the matter of your life. He struggled a bit, created some half-chances for Aston Villa.”