Although their 100 per cent home record remains intact after nine matches it was given a severe examination by Liverpool in a 2-1 win on Boxing Day.
That moved City into second place in the Barclays Premier League, just a point behind Arsenal, and with struggling Crystal Palace visiting on Saturday there is a chance for them to go top ahead of the Gunners' Sunday encounter at Newcastle.
"It was a massive win. We played against a very strong side in Liverpool and it was really important to get three points and keep the team winning their home games. I think we did a good job," Zabaleta said.
"We have to push even more now. We know December and January is one of the key points for the big teams to make a difference because we play many games and you need to try to keep winning.
"At the moment we are doing well, are one point behind the leaders and that is why Crystal Palace is also a key game.
"We are very comfortable and we feel good and have huge confidence.
"Sometimes there is talk we need to improve our performances away from home but we had a good win at Fulham and now our next game is at home to Crystal Palace so we need to have a good rest and be fit for that game."
City will look to use their dominance at home to overpower Palace but that was far from the case against Liverpool, who were happy to go toe to toe with their hosts.
On another day Manuel Pellegrini's side could have lost as Raheem Sterling had a goal wrongly disallowed for offside and Luis Suarez had claims for a late penalty waved away.
The fact City were able to restrict the Premier League's leading scorer's chances in front of goal was a key factor in their victory.
"They have fantastic players, especially up front with Luis Suarez - who is probably the best striker at the moment, Sterling and (Philippe) Coutinho," Zabaleta said.
"They also try to play good football from the back and I think they did well but at the end we took big chances and it was great to score two goals.
"When you play against the best players, you always try to keep them quiet.
"If we look at the overall performance of Suarez I think we kept him very quiet and that is why we need to give credit to the back four."
Nine straight wins means the Etihad is formidable place for opposition teams to go, but Pellegrini is conscious they need to avoid complacency.
The Chilean is not happy his side have to play so soon after the Liverpool match and his players unusually underwent a recovery session immediately after the game before all being taken back to the team hotel to prepare for Saturday.
"What I think we must have at least 72 hours from this game to another," he said.
"All the other teams at the top of the table apart from Manchester United (and City) play 72 hours after.
"These days we play so closely the rest of the teams must be the same, although not a winter break, no."
Having been regularly attacked by Liverpool Pellegrini must prepare his side for another approach from what will be a pragmatic approach from a team managed by Tony Pulis.
"Palace are a different challenge but maybe everyone thinks we are going to beat them because it is an easy game," he said.
"All the teams in relegation positions provide tough opposition.
"We must now try to recover as soon as we can and we will see what happens on Saturday but I don't think it will be an easy game.
"We will start talking about not making a mistake and thinking it will be an easy game."