The Sky Blues completed a double of Charlton Athletic at the Ricoh Arena yesterday afternoon on Boxing Day.
City took the lead just before the half-time whistle, when Jordy Hiwula was on the end of a Conor Chaplin cross.
The Addicks equalised just before the hour mark when Darren Pratley nodded past Lee Burge.
However, with seconds remaining of the 90 minutes, Tom Bayliss fired the Sky Blues back into the lead.