City - who had won 19 of their previous 20 matches in all competitions - started Monday's clash strongly, but Chelsea slowly worked their way into the game and sealed a 1-0 win thanks a superb Branislav Ivanovic strike just after the half-hour mark.
|29/1||Man City are 29/1 with Betway to win 5-0 over Norwich|
The result represents the first time since November 2010 that City have not scored at home in the Premier League, a run of 61 matches, but Pellegrini is confident his side can recover.
"For Chelsea it was a decisive game, for us it was an important one," the Chilean told Sky Sports. "We're still two points behind Arsenal.
"It was a very tough game, they score a beautiful goal but we had clear chances at least to draw.
"We couldn't do and they had two or three chances against the post. It was a very close game, they played well. We are not going to have any problems [bouncing back]."
City were dealt a blow before kick-off with an injury to Fernandinho - and Pellegrini admitted their task was made harder without their Brazilian midfielder and other high-profile absentees.
"Missing players [made it tough]," he added. "To play without Sergio Aguero, Samir Nasri, Fernandinho and Javi Garcia was difficult. Fernandinho was a big loss."