In my opinion, Cesc, Xavi and Iniesta must start against Madrid. Xavi and Iniesta are easy to see but I think the form that Cesc is in merits him starting against Madrid. At the same time, we cannot play either our 3-5-2 nor our 3-4-3 because Madrid would destroy us on the break. 4 at the back is an absolute necessity so what I want Pep to run is in shape a 4-4-2 diamond, but in reality it would mold more into a 4-1-3-2/4-3-3. here is what I am thinking:
Valdes; Dani Alves, Puyol, Pique, Abidal; Busquets; Xavi, Cesc, Iniesta; Messi, Villa
key players tactically are Dani Alves, Cesc and Villa. assuming that Mou fields his best starting XI in a 4-2-3-1 the way he did against gijon, this formation could work on in our favor pending these three things:
1. Dani Alves has to play tactically disciplined, especially when Ronaldo is on his side. he needs to play perhaps a bit more conservative than he usually does and will have to pick his times to go forward with a little more careful discernment. we still need the wide runs he makes especially since he is linking up Xavi and Messi on that right hand side he would have with my formation, he could terrorize Marcelo but he cant afford to allow Ronaldo to do the same, so he has to be picky on his runs. we have seen him do this before during the CL Semi's last year though, and he can do it again.
2. Cesc has been on a great run of form for the last few games and he deserves to start against Madrid, considering his spectacular performance against Madrid in his first game as a Barca player. I think he is one of the players who Mou doesn't quite have a read on for how he fits into the team and he could be the player who could make the breakthrough for Barca. As long has he keeps those darting runs into the box, he will force Xabi Alonso or Khedira back, freeing up more space for Xavi and Iniesta to settle the ball right outside the box and tikitaka the ball around Madrid's box and slow down the pace of the game from the fast paced game they want to play against other teams. key is Fabregas needs to come out and help support Xavi and Iniesta on D though, and keep Madrid honest. The linch-pin to this formation.
3. Villa played his best game for Barca against Madrid last year in the 5-0 triumph due to the amount of space and freedom he was given on the left hand side, where he got us two goals. he has played his best game for Barca in the last month when he got the same amount of space against vallecano on the left and he gets the same freedom with Spain that results in better performances from him. With this formation, he will have the freedom to roam and have tactical significance due to his ability to put pressure on Coentrao and have more room to make runs for Xavi and Iniesta. it might be a slight gamble to start him over asexsis but if it pays off, and he puts in another vintage performance, it could really boost his confidence and be a huge reason why we get the old Villa back.
Messi will be Messi, regardless of where he plays, so I think if he could be shifted back into the RF position to allow Villa room to breath instead of being choked on the LW and give Cesc more room to run into. But with Cesc, linking up with Messi, Villa and Xaviniesta and Dani Alves linking up with Messi and Xavi, Barca can most importantly slow Madrid down offensively and take a lot of the sting off of Madrid's most important attacking attribute: their speed. This should slow down Madrid and force them to play into our impost. Barca I think if we play this formation to its potential, even with Madrid in the fantastic form they are in, we can still come out with a win over Madrid, i see it as 2-0 Barca, Villa scoring one, Cesc scoring the other.