The Italian has been pleased with the performances of his goalkeeper so far this season and is not considering a change between the posts for captain Iker Casillas
Los Blancos recorded a narrow 1-0 win over Granada on Monday night thanks to a Karim Benzema goal in the first half but the major talking point was again the decision to leave Casillas on the bench.
The Spain No.1 was discarded by Jose Mourinho at the Santiago Bernabeu this season and, though many expected him to reclaim his starting berth under Ancelotti, the Italian has instead opted to stick with Lopez - a decision by which he is happy to stand.
The Madrid coach told reporters after the game: "Diego Lopez played the first game, he played the second. He's playing well, nothing more. The pressure is fuel to me [regarding the focus on the decision]."
Monday's victory was their second in as many league outings and Ancelotti reserved special praise for Benzema's goalscoring start to the season after grinding out the three points.
"Benzema is playing well and scoring. He has started well in the league," he enthused. "The team was balanced. Luka Modric and Isco played well. Isco had to sacrifice a bit because he can attack more. The work of Di Maria was important."
The former Paris Saint-Germain boss, who only took over the reins in the Spanish capital over the summer, then revealed that he had observed Barcelona's narrow win over Malaga with interest.
"I saw the Barcelona match and it was also difficult for them," Ancelotti remarked. "At the moment the most important thing is to get points and work for the short term."