A brace each from Alvaro Negredo and Edin Dzeko and a strike from the returning Sergio Aguero sent Manuel Pellegrini's side through to the fourth round where they will meet Watford at home on January 25.
Negredo opened the scoring in stoppage time of the first half when heading home Jesus Navas' clipped cross before adding a second two minutes into the second half when he received a through ball from Aleksandar Kolarov before chipping home.
Dzeko sustained his recent scoring form by giving City a third in the 67th minute when finishing a clever cut-back from Navas before substitute Aguero, back from a calf injury, lashed home from close range.
Bosnian ace Dzeko then tallied his 15th of the campaign in the 79th minute when sweeping home another Navas cross to take City's goal tally to 99 for the season.
2013/14 FA Cup scores - third round
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