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It's over 11 years since Victor Valdes made his first-team debut in a Champions League qualifier against Legia Warsaw, and unsurprisingly he kept a clean sheet. In the 2003/04 season, he emerged as the sides No. 1, helping the club to win the league title after a six-year wait. Since then, he has held down the position to great acclaim.

There's a misguided opinion among some supporters that anyone could play in goal for Barcelona, but few goalkeepers in world football possess the same ability with their feet, concentration levels or reading of the game as the 31-year-old. It's no longer just about keeping the ball out of the net, the term "sweeper-keeper" was penned for players of Valdes' ilk.

Valdes rejected a new deal 12 months ago, and he confirmed his desire to leave in May last year when his contract expires this summer via BBC. That led to speculation he would then be sold for a transfer fee, but the window closed at the end of August with Valdes still between the sticks at the CampNou. This meant that director of football Andoni Zubizarreta, also a former Barca keeper, had a year to find an adequate replacement.

Current No. 2 Jose Pinto is now 38, and his unimpressive displays recently mean that a new purchase is essential. Liverpool's Pepe Reina, currently on loan with former manager Rafa Benitez at Napoli, is perceived as one option, but his drop in form over the last two years means Barcelona have their reservations about making a move for the former "La Masia" graduate. Reina may have to reassess his options at the end of the campaign, perhaps making his time in Naples more permanent.

Thibaut Courtois is also a possibility, with another former Atletico Madrid shot stopper, Abel Resino, confident he would be a good choice. "He’s young, quiet, good with his feet, although not as good as Valdes," he told Mundo Deportivo, per Football Espana. However, it's unlikely Chelsea would sanction a sale without the Belgian ever playing in the Premiership and given how the youngster has progressed at the Calderon.

Marc-Andre ter Stegen of Borussia Monchengladbach now appears to be the firm favourite. The youngster has all the attributes to emulate Valdes and spend the next decade in Catalonia. Quick off his line, single-mindedness and a more than adept passer seem to make him a good fit for the role. Gerardo Martino's direct variant on the style and philosophy is no problem either, due to his quality distribution over a longer distance.

"Despite his youth he is strong enough to go in the Barca goal. Ter Stegen can withstand pressure and has a great personality. He’s one of the leaders of our team despite his young age," teammate Alvaro Dominguez explained to Sport (via Football Espana). The Spanish centre-back continued his praise, saying, "He’s very quiet in his personal life, focused on football and training well. He’s a well-rounded person."

With his club confirming the news that Ter Stegen has turned down a new contract, then a transfer to Spain seems ever closer. The German is more than aware of Barcelona's interest and appears to be sending out a message of intent to the club. Patience will be needed should he get the gig in time for next season, as the pressure at the biggest sides can consume some young men. But as David De Gea has shown at Manchester United, any early errors or doubts can be put to bed with a strong mentality.

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Dealing with crosses is one area for improvement, after Joey Barton scored from a corner while playing for Marseille in a Europa League game against Monchengladbach. Barton admitted while serving as a pundit on BT Sport that his coach, Elie Baup, had told him about Ter Stegen's vulnerability in this area.

He wouldn't be on his own with experiencing troubles from set pieces at Barcelona, but Martino could help iron out this problem as he constructs a new back four.