Analysed: Sergi Roberto is effectively plugging the gaps in Barcelona's squad

Barcelona may have been banned from registering players for the last two transfer windows, but it didn't stop them from buying players in August. Arda Turan and Aleix Vidal both joined in the summer from Atletico Madrid and Sevilla respectively, despite knowing they couldn’t play until January. The lure of the Camp Nou was too strong.  

But subsequently, criticism over the depth of talent in reserve – or lack of it – has been a constant theme of the campaign, after the Catalan club surprisingly allowed Pedro, Gerard Deulofeu, Ibrahim Afellay, Adama Traore, Alex Song and Xavi to leave together. It’s meant manager Luis Enrique has been short in both midfield and attacking areas.

The problems in defence have mainly come in the form of suspensions, plus the inevitable breakdown of Thomas Vermaelen. Add major injuries to key players Lionel Messi, Ivan Rakitic and Jordi Alba in the opening few months, and the squad has been left looking rather bare at times.

Barcelona may have won the treble last season, but clubs have historically invested heavily after completing this feat. Manchester United signed Ruud van Nistelrooy after they secured three major trophies in one campaign, while Barça themselves bought Zlatan Ibrahimovic for almost €70 million in 2009.

Two years ago, Bayern Munich snapped up Mario Gotze and Thiago Alcantara, and then brought in arguably the most important signing of them all in manager Pep Guardiola. Only Inter failed to invest sufficiently in 2010, which, along with the transition from Jose Mourinho to Rafa Benitez, prompted a big drop in standards.

Quality from within

Regular game time has made a huge difference to me – psychologically as much as anything else

For Barcelona this time around, it was the perfect opportunity for the club to return to their philosophy and promote from within; a chance for La Masia graduates to stake a more permanent claim for a place in the side.

One player who’s taken his opportunity is Sergi Roberto. The 23-year-old had made just 14 starts for the Blaugrana before this season after making his debut for the first team in 2010, but has already reached eight appearances just three months into 2015/16.

"Getting more playing time has really boosted my confidence," he confessed recently. "In the past I might have to wait a month between matches, and regular game time has made a huge difference to me – psychologically as much as anything else.

"If you're only getting the odd game and you have one bad day, then you might never be picked again. Now I can allow myself to take a few risks because I'm playing regularly."

Positional sense

Sergi Roberto is a player who I had with Barca B. I know what a top-quality player he is

The midfielder has profited from the misfortune of injuries to others, and his adaptability to a number of positions. Only 19 minutes of the new La Liga season had passed when Dani Alves had to leave the field at the new San Mames. Roberto replaced the Brazilian at right-back and grew into the role enough to be picked from the start against Malaga and Atletico Madrid.

"Luis Enrique initially suggested the change to right-back casually during the summer and then put me in this new position while we were on our tour," said the midfielder.

"He told me how he was signed as a striker and ended up playing full-back, midfield and just about everywhere else. Previously, I was always an attacking midfielder for Barça and had never played full-back in my life. But I'm adapting well and am fine with it now."

Last season, Roberto covered for Sergio Busquets as the holding midfielder. There are certainly similarities in the way they both progressed to the senior side, if not stylistically. Busquets was tutored by Guardiola in the B team before he landed a regular spot alongside Xavi and Andres Iniesta.

"Sergi Roberto is a player who I had with Barça B. I know what a top-quality player he is," Enrique affirmed.

Fill me in

Enrique’s trust has been evident when resting his first-choice line-up. Croatian Rakitic started from the bench against Celta Vigo, as Roberto filled in on the right of central midfield, and then returned to right-back the following match against Las Palmas.

Perhaps the defeat to Sevilla highlighted his flexibility the most, as he played for an hour at right-back before moving to the left central midfield position for the final 30 minutes in place of Busquets, who Enrique had notably used further forward in this game.  

He scored as a substitute against Bayer Leverkusen, when he first drew three players to the ball before hitting a sideways pass to Alba. His following run into the box earned him a simple tap-in after Leverkusen goalkeeper Bernd Leno had initially saved from Luis Suarez.

Roberto started the next two Champions League matches against BATE Borisov – the second on the right wing in a front three with Suarez and Neymar, in a 3-0 victory at the Camp Nou.

Back in the league, it was Iniesta who stepped aside for the youngster against Rayo Vallecano and Getafe, who laid on two quality assists in the latter match. Then, he covered for the injured Rakitic before the international break in the win over Villarreal.

Spain calling

Only Neymar and Messi have completed more dribbles per game in the squad

It's extraordinary that Roberto looks equally comfortable playing a clever incisive through-ball as he does making a last-ditch tackle to prevent an opposition attack.

His ability to perform at a consistent level in recent weeks, despite all the positional movement, has led to firm interest from Spain manager Vicente del Bosque. "Sergi could well go to the European Championship with Spain next summer; he's well within our thoughts and plans," admitted Spain’s assistant manager, Toni Grande. Enrique added: "It's difficult to play for any national team, especially the Spanish team, but I think he's more than ready."

Only Neymar and Messi have completed more dribbles per game in the squad, while Adriano, Javier Mascherano and Busquets are the only three who average more tackles.

Few players could hope to make such an impact in a short space of time for the reigning Spanish and European champions, and Roberto’s remarkable achievements should extend beyond the January transfer window when Enrique can call upon the services of Turan and Vidal.

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