Los Blancos returned to the summit of La Liga with the thrashing, having claimed 16 points from six games, with an impressive 21 goals scored.
Karim Benzema had put Real ahead after three minutes, before Asensio hit a first-half double.
The 25-year-old former Mallorca man completed his hat-trick in the 55th minute, with Benzema grabbing another and Isco rounding out the scoring in the 84th minute.
(Asensio) can do very well there, in that position between the lines, Ancelotti said.
Its a position in which he can do a lot of damage, because he has quality, he shoots very well, he combines very well with the forwards. I think this is his position.
Ancelotti was delighted with his side’s display, putting down a statement to the competition.
We started well, Carletto said. We alternated play a little and played with a lot of intensity.
“We were more aggressive and on the front-foot. We hadnt worked on it, but we did talk about it and the players understood it well.
“The players who hadnt played much were prepared and thats a good sign for the whole squad.”
Elsewhere on Wednesday, Villarreal won 4-1 over Elche and Sevilla beat Valencia 3-1.