"We tried hard to win but Stoke, at the moment, are very sharp physically," he said.
"We looked a bit jaded because we have played a lot of games recently.
"At the moment we are suffering. I don't believe it is confidence; we put a lot in on Wednesday night and we play again in midweek in Europe.
"We have very bad injuries. We have Adebayor, Walcott and Sagna as well as one or two others who have knocks, but that's the kind of game we played here.
"When you are not as sharp, you are less agile and you can't get as quickly out of tackles."
He added: "We had lots of possession against a team who defended very well and was very well organised, but we were not sharp enough to create chances with the possession we had."