Gareth Bale and James Rodriguez were both twice denied by the hosts??? goalkeeper Jan Oblak as they played out a goalless draw at the Vicente Calderon on Tuesday night.
Real had failed to beat their city rivals in the six meetings since their triumph over Atletico in the Champions League final last season, and they tried hard to break that run with a dominant first-half display.
But Diego Simeone???s side improved vastly after the break, although couldn???t find the net either, and the two go into the second leg all square ??? something Ancelotti was left disappointed by.
“I think that in the first half we deserved more than to be 0-0 at half time,??? he told reporters.
???We need to highlight the performance in the first half which was fantastic.
“In the second half, Atletico pressured more and the game was more even.
“It isn’t a brilliant result but we have confidence for the return leg, especially based on the first-half performance.”
Atletico travel to Deportivo before Real face Malaga in La Liga on Saturday, with both games live on Sky Sports as Ancelotti???s men look to keep the pressure on leaders Barcelona.
The two then meet again April 22 in the second leg at the Bernabeu, also live on Sky Sports.