He needs rest, definitely slightly off of it. Needs to recharge.
Also I think part of him not having such great games is having no one up front to pass to. We need to sort out exactly how we're going to utilize Fabregas' playmaking ability.
Whenever we speak of subbing players for Fabregas, we always mention Iniesta or Villa but we rarely dare to mention Xavi. Xavi isn't always on peak form either, and there are times when I definitely think Xavi deserves to rest (also to recover for bigger games).
I think Cesc + Iniesta midfield has worked very well this season and could work very well for us in creating goal chances.
Villa - Messi - Tello/Sanchez/Pedro
Iniesta- Busquets - Fabregas
Cesc and Iniesta are 2 of the most creative midfielders we have in creating chances, both probably more creative in the final pass than Xavi at the moment. Xavi is more of the metronome, orchestrator, while Iniesta and Fabregas dribble or create lob passes/through balls like none other. Having those 2 linking up with the offensive-goalscoring attacking play of Villa and Tello (2 true forwards) I think would be highly productive.
Of course if we are to try this we should only do it in Liga games and less important games, just to feel it out. Surely Xavi has to play in our most important games against our best opponents but I think Cesc + Iniesta midfield with attacking forwards up front is not a bad substitution at all. Especially when Xavi is off form and Cesc is on fire.