Pellegrini said: "It was a really good performance.
"The team played really well during the 90 minutes, not only the first half.
"Normally when winning 4-0 at half-time, in the second half a team finish or stop.
"But the team continued playing exactly the same and that's very important for me."
It was City's biggest top-flight victory since 1968 and their most emphatic at any level since hammering Huddersfield 10-1 in the old Second Division in 1987.
On some of the fluid moves involving the likes of Aguero, Silva and Samir Nasri, Pellegrini said: "It is the way we work every day.
"It is so important for me to see the way I want them to play.
"They are very good technical players when they move the ball quick and move into space, it is very difficult for our team not to score so we must continue the same way."
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