United want to wrap up the championship before the last day of the season and that means the manager Ferguson expects his team to beat neighbours and challengers Manchester City at Eastland's on April 30.
United were beaten 6-1 in the corresponding fixture at Old Trafford earlier this season and they will need to avenge that defeat if the Red Devils are to land their 20th league title.
United keeper De Gea said: "Mr Ferguson has insisted just one point could be decisive and we want to keep our destiny in our own hands. Success is down to us and we cannot fail.
"We have spoken in the dressing room and the numbers are clear. We want to win all our matches and try to make sure we clinch the title before the last day."
United will move four points clear at the top of the league if they beat relegation-threatened Wolves on Sunday, with second-placed City not playing Chelsea until Wednesday.
Having crashed out of the Champions League and subsequently the Europa League, the title is the only trophy now available for United to win.
"It is now our duty to maintain our lead in the Premier League until the end, De Gea told The Sun.
"Winning the title will help us forget the bitter taste of defeat in the other competitions so, from this weekend onwards, I want the fans to see the very best version of United."