The Citizens impressed against the Gunners before securing a 2-1 win against title rivals Liverpool on Boxing Day, allowing the Eastlands outfit to momentarily top the Premier League table.
We scored six goals and it was a key game in December
Arsenal have since reclaimed first spot in the English top flight – but Pellegrini stressed the significance of his side beating the current league leaders in a testing month.
“It was important,” Pellegrini told City’s website.
“Before we started December we were six points behind Arsenal. It’s too many points if you’re trying to fight for the Premier League.
“We’re also including Liverpool and Chelsea and we were five points behind them.”
He added: “To record those points was very important for us. More if you have to play Arsenal. We scored six goals and it was a key game in December.”
Despite the importance of beating Arsene Wenger’s side, Pellegrini picked City’s 3-2 win against Champions League holders Bayern Munich as his favourite result in December.
“Of course Arsenal was one of the games I remember,” Pellegrini added.
“I think it was very important to beat Bayern Munich in Germany. We made five or six
“We were losing 2-0 in the first 10 minutes, so to win 3-2 was not an easy game. We had the character and personality to beat Bayern.”
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