Their league triumph last year showed what City are made of and Hart says the ingredients remain the same.
He said: "That belief is still there. We have to be optimistic. We know we are doing the right things, we are tried and tested."
Hart, 25, denies the mantle of being champions is weighing City down as they become a big scalp for each opponent.
The England keeper added: "We won it, it was hard and this is my first attempt to try to defend it. It is going to be tough but then again it was ridiculously tough last time.
"It's the same pressure we have always put on ourselves, inside pressure that pushes us forward.
"We have been there to be shot at for a while. For financial reasons people have had a point to prove against City - a draw against us is a result because we are a good side."