Pellegrini brought five new faces into the team after the midweek draw with Everton in a bid to keep players fresh for the busy schedule. And the Chilean was left pleased with his tactical decision.
"We have to play so many games in January and it is very important to have the whole squad involved in what we are doing if we are to remain a competitive team in all of the competitions," the boss explained at his post-match press conference.
"To have made so many changes but win the way we did is very useful," he added as City work their way through an eight-game January.
It was Crystal Palace who had the best early chances, but Fabian Delph opened the scoring with a speculative drive from distance. The goal opened the game up and allowed City to eventually add a second, third and fourth to seal a comfortable victory.
"I think it was important to score the first goal. When we are able to score the first goal, we know we are going to have more space," Pellegrini commented.
"We are used to playing against eight or nine players behind the ball. We don't always score but with space, we are more dangerous. The two goals gave us more space as they had to go for the draw. That allowed us to use that space and score two more."
Delph was one of the five squad players the manager called upon, telling MCFC.co.uk that while he was awarded the stadium man of the match, "there were five, six, seven or eight top performances out there".
The midfielder added, "I think I needed to put in a good performance to help the team and thankfully, I've done that."
The game also marked a big milestone for Pablo Zabaleta who made his 200th City appearance on his 31st birthday.
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