The 31-year-old, who rejoined Real in January following an injury to Iker Casillas, kept a clean sheet in Monday's 1-0 win at Granada as Ancelotti's side followed the likes of arch-rivals Barcelona by collecting maximum points from the start to the season.
Despite making a full recovery from a hand problem, Casillas has not featured in a competitive game for Real since the end of January, prompting speculation regarding his future and reports he is a transfer target for Arsenal and Paris Saint-Germain.
Ancelotti is happy for Lopez to continue in the side as Real prepare to face Athletic Bilbao on Sunday.
"Diego played the first match (a 2-1 win over Real Betis), Diego played the second. He is playing well at the moment and that's it," said Ancelotti.
Leaving a player as experienced as Spain captain Casillas – who has won the FIFA World Cup, UEFA European Championship, UEFA Champions League twice and the La Liga title five times – on the bench arguably puts Ancelotti under extra scrutiny following his arrival at the Bernabeu.
Not that the former Milan, Chelsea and Paris Saint-Germain manager is concerned by being in the spotlight.
He added: "I am not crazy, never crazy.
"The pressure is something normal when you are a coach I have experience and to me the pressure is like petrol.
"For doing our job we need petrol. The pressure for me is energy."
Karim Benzema's second goal of the season earned Real victory over Granada, and Ancelotti admitted it was a nervy evening.
He said: "We couldn’t score the second goal in the first half and after when the result is just 1-0 is not easy to control the match.
"It's normal to suffer at the end. The important thing is the result, which is good.
"I think as well our way of playing was good at high level pace. The team were compact and our defence played well. They tried their best and I am really happy."
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