Silva declared the 4-1 defeat the worst performance of their season.
He said: "In general, I agree it was the worst performance. You can talk about a lot of things in the match, and I want to focus really about what we can control.
"Until the first goal we didn't perform much as we must do. We were too slow until then, and after that, for the second and the third we made mistakes which you cannot make at this level.
"I don't want people to say, 'Marco only wants to talk about referees.' Congratulations to our opponent, they won the match. We will keep working hard, the Premier League is hard.
"It's important in this moment, and of course this game is done and you can't change the result, that we keep focused in our job and prepare for the next game.
"It was a tough afternoon, we understand easily what we did wrong, our players are already understanding it from when we talked after the game.
"We weren't the best team in the Premier League a few games ago and we aren't the worst now."