Fábio Coentrão, Ángel Di María and Sergio Ramos are suspended for the match. Marcelo could start but he has played only one half of football since breaking his foot. Pepe is injured and Iker Casillas's hand is being held together by two metal inserts after surgery.
With the first-choice and part of the second choice defence gone, and our captain out, it is quite literally anyone's guess who will start in defence. Arbeloa is a certainty. The left and the centre are an open question. Logic would dictate that Raphaël Varane play, but José Mourinho may want to go for experience in the centre of defence and replace him with Carvalho. Varane can also play as a full-back, but Michael Essien could start. He has, of course, a rather impressive record against Barcelona: he has never been beaten by that team. Though one should note that all his outings against them were in midfield.
In di María's place, José Callejón is expected to start. Though Mourinho has gone with two strikers against Barcelona in the past.
Of greatest interest will be who starts in goal.
In general however, the line-up is anyone's guess. It will be lacking 5 regular starters, but that is all we know.
Diarra - who was league, Super cup and Copa del Rey winner with Real Madrid - had his own memories of the Clásico, and shared them with the club's in-house media:
The team has to come out onto the pitch with ambition and enthusiasm and show everyone what Real Madrid is made of in front of their supporters. This way we can achieve great things for our fans and go into the second leg with confidence. I hope that Real Madrid wins tomorrow and that it's an exciting game.
You are aware that this is unlike any other match. Inside the dressing room the footballers are under a lot of pressure, but they're also confident about the match and give it their all. The last few minutes before the clash are just spent thinking about what a great opportunity this is to show everyone why you play for Real Madrid.
Diarra, who left the club for Monaco in January of 2011, attended the training session and spoke with his former teammates.
Mesut Özil, Karim Benzema & Notes on Media Coverage of Cristiano Ronaldo
The distinction of playing for Madrid was also central to Mesut Özil's comments. Speaking to Madrid sponsor BWIN he expressed his pride at being allowed to play "at the best club in the world" and said the following:
We will do everything we can to win. It is the best derby in the world and the whole planet will be following it. It is always something special for us. The players want to show what we can do and always play against the best. Obviously, you always want to win this type of match, especially for the fans who support us all year.
I am very grateful to be able to play for such a big club. My first match for Real Madrid was very special for me. But the best moments are when you win trophies with the club. For example, the [Copa del Rey] final against Barcelona, when we beat them in the Super Cup or winning La Liga, those stay in your memory forever.
Özil (along with Ronaldo) has been a press favourite for the past two weeks, with several features in Marca and As praising his elegance and intelligence and noting the unusual and marked affection the crowd in the Santiago Bernabéu has developed for him.
He was asked to comment on these displays of affection and on the coverage he and Ronaldo have enjoyed this week.
We know about Cristiano Ronaldo's potential. He is one of the best players in the world and in recent years has shown how important he is for our team. But at the end of the day this is about the team, not Cristiano or any other player. Naturally we know his strong points, we need him, but we have to work as team to be successful.
My aim is always to offer my all that I can on the pitch. I enjoy playing football. I enjoy being on the pitch and having the ball. I am proud that they say things like that, of course.
Our aim is to win the match and dedicate it to our fans...
On the subject of Ronaldo, who holds the record for number of consecutive times he has scored in a Clásico (7 times in 6 consecutive games) the greatest speculation is whether he will break his own record.
Karim Benzema also spoke - not to the sponsors but in a press conference. He was asked (as I have noted, it is the dominant theme - one might almost say the only theme - in news coverage this week that has centred on the players) on teammates Ronaldo and Özil.
He's a great player. He's got a lot of skill, he's really good technically and it's important for us that he's here. I'm really happy with him.
For us he's the best player in the world. It's good that he plays for Real Madrid.
On tomorrow's match:
A Real Madrid-Barcelona is the best match in the world. We're two amazing teams. It's always a difficult game and the fans are ready to see a good game. The Clásicos are always different matches, but tomorrow we aim to score goals and win. Although we know that it's a two-game round, we're playing at home tomorrow and we want to play well and win. We played really well against them in the second round of the Supercopa and we hope for another victory.
On the injuries to the squad, Benzema was suitably optimistic:
It would be better if everyone was available, but we're a good group and a solid squad that's going to try to win tomorrow.
And he displayed his usual loyalty to the coach. Asked about "tension" in the locker-room:
We have no idea why they [the press] say things like that.
We end with the man who appeared more often in a Madrid shirt than any other foreign player and who won 3 Champions Leagues, 4 League titles, 2 Intercontinental cups, 1 European Super cup and 3 Spanish Super cups with the club - the greatest left-back and free-kick taker in history: Roberto Carlos.
Roberto Carlos posed for photographs with former national teammate Kaka and his heir in the left-back position: Marcelo Vieira and had the following to say about the match.
A Clásico is the best game of the season.
There are two memories which will always remain with me. A game I played for Brazil against China, when I scored my first goal, and the goal I scored from a free-kick against Arnau in a Clásico at the Bernabéu. Those goals defined my career.
When you enter the field, you are so focused on the game that you only hear people shouting and celebrating. Many hours later, you watch the footage on the television and you remember what you experienced. You have to be at your best to win the game.
Watch Roberto Carlos's goal at this link. It was a beauty.
Good luck to the boys tomorrow! Hala Madrid!