Ahead of Barcelona’s crucial top-of-the-table clash against Atletico Madrid at Camp Nou on Saturday afternoon, coach Luis Enrique will finally be able to use his trump card. After half a season of waiting, Arda Turan is up and running – and already excelling. Turan debuted for Barça this month despite being signed last summer, because of the club's ban on registering players.

Turan is at home out wide. This is crucial, because it means Lionel Messi, playing on the right of the front three, can drift inside into central positions without Barcelona losing their width

It means he’s “like a new signing”, but realistically he’s actually better than that – new signings take time to settle at a new club, and early performances are often inconsistent because they’re not up to speed with the team’s approach. Turan has experienced five months of training sessions ahead of his debut, and therefore such an immediate impact doesn’t come as such a surprise.

Odd one in

Turan isn’t a typical Barcelona player. At Atletico he played a curious role in Diego Simeone’s system: somewhere between a wide midfielder and an ‘interior’, to use a Spanish expression.

He would defend the wide zone effectively, but surge forward diagonally when possession was won, creating and scoring from central positions. He was a good tackler and an excellent dribbler, and therefore was perfect for the transition-based game that Atletico played en route to the 2013/14 league title.

There’s no typical wide midfield role in a four-man midfield, because they play a 4-3-3 system and certainly won’t change that merely to accomodate Turan

Barcelona are a different side entirely. For a start, there’s no typical wide midfield role in a four-man midfield, because they play a 4-3-3 system and certainly won’t change that merely to accomodate Turan. Therefore, he can play one of two roles – either as one of the three central midfielders, or as an outside-forward. Against Malaga on Saturday, a 2-1 victory, he did both – and was Barça's best player.

Compared to Barcelona’s previous options, Turan brings different things to the two roles. Starting right of the midfield trio, it was noticeable how frequently he drifted towards the right touchline, rather than holding his position close to the centre circle. This is something that often happens for Barça, with Ivan Rakitic moving out wide, but the Croatian isn’t entirely comfortable in that position – he’s more of a playmaker than a winger.

Turan is at home out wide. This is crucial, because it means Lionel Messi, playing on the right of the front three, can drift inside into central positions without Barcelona losing their width.

Some degree of width comes from Dani Alves, certainly, but he’s less energetic than at his peak five years ago (and was rested against Malaga with another newcomer, Aleix Vidal, deployed at right-back) which means Luis Enrique wants a wider, more structured midfield. Indeed, at the start of the second half, Turan played almost permanently wide, with Messi more like a No.10, and Barça setting up like a 4-2-3-1.

Keep ball

The most impressive thing about Turan’s performance at La Rosaleda on Saturday was his reliability in possession. In a game where Barcelona’s passing was atrocious by their usual high standards, particularly in deep positions, the Turkey international gave the ball away just once in the entire game.

In the second half, Barcelona went 2-1 up and Luis Enrique decided he wanted to change his system slightly. Therefore, he introduced Rakitic in Turan’s role, and moved Turan to a left-wing position, with Munir departing. This effectively gave Barcelona an extra midfielder, with Turan dropping deep from a left-wing position to help dominate the centre of the pitch.

A player in this ‘floating’ role has often been crucial for Barcelona over the years - Pep Guardiola liked using Andres Iniesta in a narrow left-sided role in big games, while earlier this season a key player in the 4-0 thrashing of Real Madrid was Sergi Roberto

A player in this ‘floating’ role has often been crucial for Barcelona over the years – Pep Guardiola liked using Andres Iniesta in a narrow left-sided role in big games, while earlier this season a key player in the 4-0 thrashing of Real Madrid was Sergi Roberto, playing that role from the right and getting into excellent positions between the lines. But Iniesta dislikes playing in the front three, while Turan is simply an upgrade on Sergi Roberto.

It remains to be seen whether Turan can hold down a permanent role in Barcelona’s starting XI – he’ll probably feature regularly because of rotation, but in various different roles. More performances like the one at Malaga last weekend, however, and both Rakitic and Iniesta will need to up their games.

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