Manchester City manager Mark Hughes believes his side have added an extra tool to their armoury and become dangerous from set pieces.
Fulham were dismantled after extra-time in the Carling Cup following a headed goal from skipper Kolo Toure after a corner from substitute Martin Petrov.
Earlier in a similar situation Gareth Barry had hauled City level following Craig Bellamy's delivery.
It was fine comeback by Hughes's side after Zoltan Gera had opened the scoring for Fulham with a blistering 30-yard half-volley
After the 2-1 victory, Hughes said: "We have not done badly this season - in the early part of last year we did not look a threat from set plays. In games so far we look like a team that can now.
"We have told the players where we want the ball delivered and how they need to be a bit more dynamic in the box and make sure they get first contact.
"Invariably if you get that first contact something happens for you. That is what we have tried to emphasise to the players."
Sealing a place in the fourth round was just the boost City were looking for after the late, late defeat by Manchester United on Sunday.
Hughes said: "Fulham are very well organised and got plenty of people behind the ball. It was difficult to break them down. We had to be patient.
"We stuck at it and are in the hat for the next round which was the order of the day. We are pleased about that.
"You have got to understand how much effort and how much emotion there was in the derby. The players were a little bit drained but kept going. Obviously coming from behind is difficult."
Fulham manager Roy Hodgson was proud of his second string side.
"I was disappointed we could not take it to penalties but I am not disappointed with the team as they gave me everything," he said.
"I thought we could give Manchester City a game and make it difficult for them. But we took it to an even better level.
"To find ourselves at 1-1 going into extra-time was more than we could have hoped for but we deserved it. I have got a pretty good idea now of which players I can trust."