With Flick complaining that his men didn't get much rest since some of them just returned from international duty not too long ago and now have their game with Osasuna, don't you think the performance of Barcelona will drop a bit? In other way too, if you look, 80% of the squad members are Spanish and they finished their game earlier on so what's with him making a fuss. The way Barcelona are now, I feel that even though they have just one day to get ready for a game they can still give a beautiful performance.
 Madrid and Barcelona are on the same points so winning this game is a must so that they can have an edge over their competition and even though Osasuna can cause trouble for them, I still don't think they will be so troublesome enough as to cost them the three points.