Thomas Tuchel accepted there would be questions about his team selection after Chelsea’s shock 5-2 defeat at home to West Brom.
The Blues were beaten for the first time since Tuchel took over as boss.
They led 1-0 but capitulated after Thiago Silva was sent off soon after Christian Pulisic had put Tuchel’s side ahead.
Tuchel made a number of changes against second-from-bottom Albion.
Speaking at his post-match press conference, the German said: “You will question my team selection and I will do it as well, but you have to accept that you will never know what would have happened if it had been chosen a different way.
“But it’s clearly my responsibility and I am in this loss like my players. We are very disappointed, because we hate to lose.
“We went for this selection because we had an excellent training session yesterday. We had the guys on the pitch today who finished that training session.
“I trusted this line-up and I think it was strong enough to win this game. But we were clearly rusty and sloppy. There were many unforced errors.”
Chelsea had not conceded a goal at home under Tuchel but were torn to shreds by an Albion side which has struggled to score this season.
Tuchel admitted: “Our defending wasn’t at the level we want it to be and the tactical choices for that are my responsibility.”