The Blues can move them to within three points of leaders United if they beat Spurs at Stamford Bridge with Sir Alex Ferguson's side travelling to Arsenal on Sunday.
Therefore, Ancelotti is not giving up hope that Chelsea can reel in United with four games remaining and has warned his side against any slip-ups against Spurs who are still in the hunt for fourth.
In it to win it: Chelsea manager Carlo Ancelotti has warned his players Tottenham still have plenty to fight for
The Chelsea manager said: 'We have to do our job and our job is to win against Tottenham.
'It will not be easy because Tottenham is a very good team, very strong. But I think that we want to keep open the Premier League until the last minute.
'Obviously, we have to beat Man United, we have to beat Tottenham. Wewant to fight until the last minute of this Premier League.'
Arsenal blew their title hopes at Bolton last weekend but Ancelotti believes Arsene Wenger's men still have plenty to play for as they will want to finish third.
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Arsenal are only five points clear of fourth-placed Manchester City having played a game more. And Ancelotti said: 'I think Arsenal will do their best to win. They haveless chance to fight for the title. But I think Man City behind them iscloser. If you arrive third, you don't have to play the preliminary of the Champions League.'
Spurs are four points behind Manchester City in the race for the country's final Champions League spot.
Three of those are away at Chelsea - where they have never won in the Premier League era - Liverpool and City, meaning they could be struggle even to secure a Europa League spot if their poor form continues.
But Ancelotti insisted: 'They are involved in the fight for fourth place. They will try to do everything against us because now they have a gap to close to Man City.'
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Source: Daily Mail
Source: Daily Mail