He said: "I cannot say much. You can't accuse the players of not working this evening. I cannot fault them for that, and I won't criticise my players if they work hard.
"But we have made some mistakes in defence and that is the reason that we lost. And I was disappointed that we did not take the opportunities we had. If we had scored one or two more goals in the first half then it would have been different.
"We need to score but to be fair their keeper had a good game. Palace continued to work hard in the second half and we tried to but it was not easy.
"It was not the same as the other day. We had a better intensity and we started the game well and worked hard until the end.
"But we cannot change the result now. Saturday is a Premiership game and we must now start thinking about that one."