Manchester City boss Roberto Mancini has told his players to stay grounded after victory over Manchester United.
Mancini said his side deserved the win but warned his players to be on their mettle against Newcastle United next week, with United facing an "easy" home fixture against Swansea.
"We are happy but I think that next Sunday we will have another difficult game," he told Sky Sports 1.
"They play an easy game against Swansea. I think at this moment we are top of the league, but United has a light advantage yet."
He added: "We deserved to win this game. We scored, we played well. We had other chances to score a second goal.
"I don't think they had a chance to score. But it was a difficult game because United is a top team."