The Italian coach's future has been called into question with Real failing to live up to their high standards in recent weeks.
It has been reported in the Spanish press that president Florentino Perez will sack Ancelotti if Real suffer a defeat this weekend at Camp Nou, which would leave them four points behind their arch-rivals in the battle for the La Liga title.
The 55-year-old was in no mood to play down the importance of the game when he faced the media on Saturday, but does not expect to be relieved of his duties if his side slump to defeat.
He said: "I do not feel my future is on the line. It is an important game for all Madridistas, for the club, as it is for Barcelona.
"Some say I have patience without limits, but there is a limit. However I feel good, I have felt good, and I will feel good."
Ancelotti knows Real must raise their game after losing two of their last three matches in all competitions, but is backing his players to come good.
He added: "This game comes at a very important time in the season. There is a different atmosphere. We have confidence.
"In the last period, we have not played well, not been on a good run, but my confidence in the players remains total."
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