"It's just three points, now we have 42 more points to play for," Pellegrini told reporters after the match.
"Chelsea played very well but we had important players out missing. A lot of things like this affect the result, but even so I don't think we deserved to lose the game. Today they had the luck to win.
"The race for the title is the same as it was before the match. For Chelsea it was important they didn't go six points behind us but we stay just two points behind Arsenal."
The match also saw City fail to find the net at home for the first time since November 2010.