The Brazilian midfielder will miss the midweek game against Arsenal and while the manager is confident he has adequate cover, he was keen to point how crucial the the 32-year-old's role is.
“We have replacements,” said Guardiola.
“With Yaya, with several players who can play in that position.
“But of course, Fernandinho was so important this season. He was something special for us.
“He is like Nicolas Otamendi, they are special players, so, so important for what we have achieved so far.
“He [Fernandinho] is thinking for his mates. He is not thinking about his action, he is thinking what will happen.
“He has to be clever and in physical condition and Fernandinho has absolutely everything in that position.”