The Bosnia and Herzegovina international was often a bit-part player under previous boss Roberto Mancini, making many of his appearances off the substitutes' bench.
Dzeko still managed to score 15 goals though and has looked impressive in pre-season, where he has been on target in City's Barclays Asia Trophy games against South China and Sunderland.
The 27-year-old also scored twice in their 5-3 victory over AC Milan in the Audi Cup in Munich to leave him in a more positive frame mind ahead of the new Premier League campaign.
"I feel different, better. I feel I have more confidence, the manager gives me more confidence. That is an important thing," he said.
Pellegrini has publically offered his backing to Dzeko, describing him as a "top striker" and insisting he can reproduce the form that made his name at Wolfsburg.
When asked if his support was important, Dzeko added: "Of course it is. I think you can see on the pitch how I play.
"I feel different, also because you know someone who is important has trusted you. It is good, for now it is looking good."