Eagle-eyed el Clásico may notice something unusual about Barcelona’s shirts this evening.

The Catalans are wearing their usual blue and red stripes, but there is something new on the player’s backs.

For the first time in history, Barcelona players will wear their names in Chinese letters, as the club commemorates the Chinese New Year.

The Chinese lettering will sit just below the player’s names as they usually appear.

Barcelona captain Lionel Messi was named in the team's squad to face Real Madrid in Wednesday's Copa del Rey semi-final first leg after recovering from a light calf problem.

Barcelona vs Real Madrid combined XI Show all 11 1 /11 Barcelona vs Real Madrid combined XI Barcelona vs Real Madrid combined XI Claudio Bravo Barcelona have the best defensive record in the league and the most clean sheets, Bravo has been fantastic in his debut season at the Nou Camp and is excellent with the ball at his feet - a necessity. Iker Casillas is not as bad as some would have you believe, he is a long way from what he once was. Getty Images Barcelona vs Real Madrid combined XI Dani Alves Not able to race up and down the pitch quite as he once was but the Brazilian is still a key outlet for this team and a fiery defender. It'll be very difficult finding a replacement for a very unique player. GETTY IMAGES Barcelona vs Real Madrid combined XI Sergio Ramos A great defender, although he can cross the line between aggressive and dirty if things are not going his way. Possesses great talent on the ball, a threat in the opposition box, but don't be surprised if he sees red. Getty Images Barcelona vs Real Madrid combined XI Gerard Pique Has returned to the kind of form that made him the world's best under Pep Guardiola, no matter who is playing alongside him. Brilliant on the ball, strong in the tackle and dominant in the air, he is the best both teams have to offer. Getty Images Barcelona vs Real Madrid combined XI Jordi Alba Marcelo has been a much improved defender this season but Alba is the superior option in defence and attack. His pace and energy are crucial to Barca's high pressing game. AP Barcelona vs Real Madrid combined XI Toni Kroos Xabi Alonso has been forgotten far more quickly than could have been anticipated because of the ease with which Kroos has slipped in. A true great in possession, Kroos perhaps is found a bit wanting in his defensive duties but one of the best in his possession in the world. Getty Images Barcelona vs Real Madrid combined XI Isco During Real's bad patch since the turn of the year Isco has been the one bright, consistent spot for Carlo Ancelotti. Another who is superb on the ball and has the ability to drive his team forward with his low centre of gravity. This team is perhaps a touch attacking, and Sergio Busquets will play as bigger a role as any of the stars during the game. Getty Images Barcelona vs Real Madrid combined XI Andres Iniesta Still the master. Age may have finally caught up with long-time partner Xavi but Iniesta shows no signs of slowing. Yaya Toure and Fernandinho couldn't get near him on Wednesday night and while he has lost a little bit of pace, his brain is as sharp as any in world football. AP Barcelona vs Real Madrid combined XI Lionel Messi Cristiano Ronaldo may have won the Ballon d'Or at the turn of the year but Lionel Messi has easily been the best player in the world since then. Where Ronaldo has struggled (by their standards) - nine goals in 14 matches - Messi has thrived with 20 in his last 17. Getty Images Barcelona vs Real Madrid combined XI Luis Suarez After taking a few weeks to work it out, his Barcelona debut in the Bernabeu was a real struggle, Suarez has finally clicked with his new team-mates. He may not quite be as prolific as he was during his Liverpool days but he is forming a nightmarish front three with Messi and Neymar that cannot be stopped. Getty Images Barcelona vs Real Madrid combined XI Cristiano Ronaldo Even if he is struggling a bit, are you really going to leave Ronaldo out? Messi might be in better form, but no other player comes close to striking terror into opponents as much as the Portuguese. Gareth Bale and Karim Benzema have been anonymous lately, while Neymar is unlucky to miss out.

Messi set off alarm bells after sustaining a knock to his calf during Saturday's 2-2 La Liga draw with Valencia, in which he scored twice, although he was able to finish the game after being treated.

Barca did not release a medical report on Messi's condition and although the Argentine missed Monday's training, he completed a session one day before the game. The forward was then included in the squad announced at 1900 GMT on Tuesday.

Speaking before naming his team, Barcelona coach Ernesto Valverde said he didn't want to take any risks with the club's all-time top scorer.

"The most important thing is whether the player tells you he is ready or not. Regardless of what tests say, if the player doesn't think he's ready, you have to leave him out," Valverde said.

"I'm not in favour of taking risks with so many games coming up, if the season finished tomorrow, it would be another matter. When there is a risk of injury, players play with the handbrake on and tomorrow's game is not one where you want to do that."

Real Madrid coach Santiago Solari said he hoped Messi played for the good of the game - but he added that the Argentine's presence would not affect his match preparation.

"It's always good when the best players get to play every game, but whether or not he plays will not influence the way we prepare for the game at all," Solari said.

Lionel Messi during the clash vs Valencia (Getty)

Messi was out with a broken arm the last time Spain's two biggest clubs met, back in October. But Barca barely missed their talisman, thrashing Real 5-1 in what proved to be Julen Lopetegui's last game as manager before Solari took over.

Real are third in the La Liga standings but cut their gap behind leaders Barca to eight points after beating Alaves on Sunday.