The Ivory Coast international was the driving force behind City's Premier League title success last term, scoring 20 goals from midfield.
However, following a close-season that saw speculation over his future, Toure has come under criticism for his performances at the start of the new campaign.
The 31-year-old was able to make a decisive contribution in Saturday's 2-0 win over Aston Villa, opening the scoring late on with a superb left-footed strike from the edge of the area.
Prior to that 82nd-minute goal, Toure had struggled to make an impact at Villa Park, but Zabaleta is convinced his colleague will be back to his best in the near future.
"I think it was so important for him to score," the Argentinian is quoted as saying by the British media.
"We all know how important Yaya is for the team. If he is on his best form, Yaya can do whatever he wants because he's just different class. We are at our best when Yaya is at his best.
"Last season he was fantastic. He scored 20 goals and that for a midfielder is just incredible. I would like to see Yaya scoring more goals, 20 if possible.
"We need him back to his best form in terms of passing, even free-kicks. We are 100 per cent sure we will see the best of Yaya soon.
"He should be full of confidence because we know how important he is for the team, as do the fans. And hopefully he can continue scoring goals like this."
