It is widely thought Ancelotti's job could be under threat if his team fail to overturn the 1-0 lead Rooney gave United in the first leg of their quarter-final tie last week. Regardless of that, Chelsea's season certainly hinges on the outcome of the Old Trafford encounter as their hopes of retaining their Barclays Premier League title now seem distant.
The Italian said: "I think that, obviously, Rooney is the most dangerous player in the squad. We have to pay attention to his position and his performance. We have to do better than we did in the last game. But we don't change our shape, our mentality, our philosophy to control Rooney."
He added: "We want to play our football at the best level we can."
United boss Sir Alex Ferguson has claimed Chelsea, and in particular their owner Roman Abramovich, are obsessed with winning the Champions League.
Yet while there is a feeling Ancelotti could become a victim of Abramovich's ruthless pursuit of European glory if the Blues lose tonight, the former AC Milan boss claims not to be feeling any extra pressure.
The 51-year-old said: "I think that, a lot of times, I played this kind of game with this pressure. But it's not pressure, it's excitement.
"To be involved in this game is fantastic for my job, for my career. So I'm not afraid, I'm not worried about this.
"I'm happy to have a possibility to be involved in this game, to use my ability and my skill to give to the players the skills to play at their best."
On Ferguson's comments, he added: "It's not an obsession, it's a dream. In three games, we have a possibility to play a final. At this moment of the competition it is a dream to reach the final."
Source: PA
Source: PA