The City midfielder got on the scoresheet to seal all three points for Roberto Mancini's side late on and highlighted the importance of an instant reaction after the demoralising defeat last time out.
“It was tough, after the derby loss at home we needed to respond today." Yaya Toure told Sky Sports.
“Newcastle is a good team with a fantastic manager but I think today we deserved to win because we played well and it’s hard to play here.”
The former Barcelona midfielder has a good record at the Magpies' ground, after scoring twice there last season in an important victory in the title race, and he revealed that it is one of his favourite stadiums.
He added: “It’s amazing, I’ve scored here [before] and St James’ Park is always nice. The most important thing is the three points and we have to keep going.”Yaya's brother, Kolo Toure, made a rare start for the champions with Vincent Kompany out injured and the ex-Arsenal defender praised his team-mates' mental resolve after a hard-fought victory.
He told Sky Sports: "Yes, definitely [mental attitude] was very important. After the loss against United we played a great game but they got the crucial goal.
“It’s not easy to come here, even when we were two-nil up there was danger and they were putting pressure on us. I think we showed a good response, Yaya’s goal killed the game which was really good.
“When you come to Newcastle you need to be tough mentally. It doesn’t matter what has happened, they just keep going and they have great fans that were all over us. We showed great character.”