Manchester United boss Sir Alex Ferguson said his side will not suffer from complacency despite opening up a 15-point gap over Manchester City after his side beat Reading 1-0.
After City lost to Everton earlier on Saturday, Wayne Rooney's goal was enough to win in a laboured display.
United need 13 points to win the Premier League with nine games left.
"You don't get points or medals for being complacent and we won't be," Ferguson said.
"Most of the time we have been playing well this season, but the 15 points we are ahead isn't a reflection of the performance today, it's from the previous six months really."
City won the league on the last day of last season after United let slip an eight-point lead.
But Manchester United captain Nemanja Vidic said they would not make the same mistakes this season.
"If you look at the 15-point lead, you have to say that it is a big gap and we shouldn't let anything change. We have the title in our hands but we have games still to play and some especially tough away games that are traditionally hard for us. Nothing is finished yet, but we're in a good position.
"Sometimes you can feel the fans in the stands getting nervous because they think about last season. I don't think we should allow that to happen again. We are in a good position now. We should relax and enjoy playing football. It is a good time for us."
Ferguson made eight changes to his side after the FA Cup quarter-final with Chelsea last Sunday in order to keep his team fresh and said he was concerned about his players returning from international duty unscathed.
Following the break, United will travel to Sunderland for a Premier League lunchtime game on Saturday, 30 March, followed by an FA Cup replay against Chelsea two days later.
And Ferguson revealed in his programme notes that the club would be chartering private jets for Mexico striker Javier Hernandez and Japanese midfielder Shinji Kagawa in order to get them back refreshed for a crucial period over Easter.
"Private planes are going to cost the club an awful lot of money," the Scot said in the club programme, "but it is something we feel we have to do."
The United boss added after the game: "The problem we have is a lot of the players are away on international duty and will play two games.
"Then they come back and have a lunchtime game against Sunderland and then a Monday lunchtime game against Chelsea, so why have we got a squad if we don't use it?"
Ferguson also confirmed after the game that Rio Ferdinand would join the England squad and said Ashley Young should also be fit despite coming off after a crunching challenge from Reading's Garath McCleary.