The European champions came under criticism last week after losing 2-1 to Slovakia in their second Euro 2016 qualifier, but Fabregas has called for patience.
"In difficult times, we have to try and ignore what's being said from outside. We can't take interest in such things, we have to focus on being united at times like this," Inside Spanish Football quotes the midfielder as saying.
"The journalists do exactly the opposite of what we need. There are some very good players who have left us recently, and it will take time for us to move on.
"We've been used to having good results and they've not come recently, but people think football is an easy game."
Spain return to Euro 2016 qualification action against Luxembourg this evening.