Barcelona forward Pedro Rodriguez has been ruled out for ten days after suffering a hamstring injury.
Pedro was forced off during Thursday's victory over Osasuna and, while the club say tests have shown the injury is "not majorly serious", he could miss La Liga games against Real Betis and Malaga as well as the first leg of the Copa del Rey quarter-final against Real Madrid next week.
There is worse news for 22-year-old centre-back Andreu Fontas, who is due to be sidelined for six months after he tore the anterior cruciate ligament in his right knee.
Fontas, who has made five appearances in all competitions this season, was stretchered off in the early stages of the match against Osasuna. The club have confirmed he is to undergo surgery in the coming days.
Barca are already without David Villa and Ibrahim Afellay through injury, while Seydou Keita is with Mali at the African Nations Cup.
• Midfielder Javier Mascherano insists the team are not going to give up on the Primera Division despite being five points behind leaders Real Madrid.
He told reporters at a press conference: "No, I don't know who (thinks that) but we think not. In order to continue advancing in the Champions League you have to maintain a good level in the league.
"If you are at a good level you will advance. It (five points) is a difference we would like, but we have 63 points to play for and in this game anything can happen.''
Mascherano also paid tribute to Wednesday's opponents, saying: "Madrid has great players, they are experienced and will not be easily overcome.
"We were fortunate to win the last game but one day in the future we will lose to Real Madrid.''
The Argentina midfielder also admits it would not be the end of the world if Barcelona were to lose in midweek.
He said: "It depends, because last year we lost in the cup and yet we continued with the league and Champions League and did well. It all depends on how you can respond later. Because it can affect you if you win, you can relax and not do well in the Champions League and league.''
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