Ancelotti admitted Drogba was furious at being left on Chelsea's bench.
But the Blues' boss still praised his striker, who hit the equaliser then missed a penalty.
Ancelotti said: "Didier played very well when he came on and worked very hard. But he was not happy, obviously, to not start."
Drogba also reacted angrily when his boss asked him to warm up at half-time before coming on for the second period.
The stoppage-time penalty, saved by Heurelho Gomes, would have put Chelsea top again. Instead, they have not won for five games.
Ancelotti added: "Didier showed a good reaction in the second half and played a fantastic game.
"I had wanted to play using counter-attacks, using the speed of Nicolas Anelka to create opportunities to score. We could have won with the penalty. Our blip is behind us."