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When Manchester United goalkeeper Edwin van der Sar decided to retire in the summer of 2011, supporters were rightfully worried. After all, they'd seen how difficult replacing their last legendary goalkeeper, Danish treble-winner Peter Schmeichel, had proved in 1999.

The Dutchman had represented an assured last line of defence during his six years at Old Trafford and had played a heroic part in their Champions League success of 2008. He was a safe pair of hands, and similar were needed in replacement. What supporters could certainly do without was a new Massimo Taibi.

On June 29 that year, a deal for Atletico Madrid's 20-year-old goalkeeper, David de Gea, was confirmed. After just 84 appearances for Los Colchoneros, during which time he won both the Europa League—beating Roy Hodgson's Fulham in the final—and the European Super Cup, saving a Diego Milito penalty en route, United decided he was the right man to replace the outgoing Van der Sar.

ESPN reports that on signing, United's goalkeeper coach, Eric Steele, was full of praise:

He's just a unique talent. Ultimately, I think they come around in cycles. Iker Casillas was 17 when he got in the Real Madrid team, I saw Gianluigi Buffon when he was 17... The qualities we've all seen, and the manager has seen, have ticked the boxes. There is always an element of "can they handle 76,000 at Old Trafford?" but I've seen him play at the Nou Camp, man of the match. Not fazed.

Nonetheless, a £19 million British transfer record (for a goalkeeper) was seen as something of a risk for a goalkeeper of such relative inexperience. No doubt he'd enjoyed a meteoric rise at Atleti and that he was a goalkeeper capable of such breathtaking saves that others could only dream about. But he was young, raw and his somewhat passive nature left question marks about his ability to dominate his penalty area.

Fast-forward almost 23 months and we now talk of David de Gea, the PFA goalkeeper of the year and Premier League winner.

The 22-year-old has grown, both physically and metaphorically, and has gone some way to justifying why the outgoing Sir Alex Ferguson was willing to outlay such a lavish figure on a relative novice.

The penchant for tremendous shot-stopping continues to grow , as does the staggering agility and the skillful use of his feet, both in making saves and passing out from the back.

Now, however, there is also the increased confidence in the face of opposing physicality. The benefits of a customised strength-building programme have aided his ability to deal with crosses and some of the Premier League's more physical customers.

His early days at Old Trafford seemed to be fraught with danger whenever he ventured away from his line, and his shirt appeared that little bit too big for him. West Brom away on his Premier League debut was a baptism of fire, and a shaky start eventually reached a head during a dismal 3-2 home defeat by Blackburn in late December. For a brief period he was relegated to the substitutes bench, with Anders Lindegaard taking his place between the sticks.

Nevertheless, he now appears much more comfortable in the face of such physical barrages to the extent that he may even relish such confrontations; his recent kerfuffle with West Ham and Andy Carroll acting as proof, the Spanish under-21 international standing up to the on-loan Liverpool man and very much giving as good as he got.

Without doubt he has improved in that regard and additional praise has been forthcoming, with Sir Alex Ferguson recently tipping the Spaniard to only get better in the coming years, as reported by The Guardian:

David de Gea has developed and matured as the season has gone on. We've seen a very progressive and developing young goalkeeper and next season he'll be even better.

The early lapses and mistakes that punctuated his first campaign, and that were even prevalent in the opening part of the present campaign, have slowly but surely been eradicated. The ability to make truly world-class, match-winning saves certainly remains.

Certainly there are further tests to come for the now undisputed Manchester United No. 1. But his evolution from Manchester United liability to match-winner would appear almost complete.

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