text: Keeping David de Gea at the club would be the biggest signing Manchester United could make this summer, says Phil Neville. The Spanish keeper has impressed for Louis van Gaal's side this season and has heavily been linked with a move to Real Madrid, who are looking for a long-term replacement for Iker Casillas. United have been linked with their own big-money moves for the likes of Gareth Bale and Mats Hummels, but Neville believes the club must concentrate on keeping De Gea at Old Trafford. David de Gea met Man United fans earlier in the week as part of a day organised by the club's foundation . De Gea punches the ball away during Manchester United's 1-0 defeat to Chelsea at Stamford Bridge . 'The biggest thing is David De Gea, and keeping him at the football club,' Neville told the Manchester Evening News. 'From when he first came, to how he is now, I don’t think I’ve seen a player develop and improve as quickly as him. 'I saw with Cristiano (Ronaldo), I saw the development in terms of his performance, his size, his stature and his physique. 'He’s winning football games on his own. Last minutes saves against Everton, Hull, Arsenal away - there’s seven or eight occasions where he has won United games which just shows you that he is world-class.'
target: David de Gea has been integral to Man United's success this season .
  Spanish keeper has been linked with a move to Real Madrid in the summer .
  Phil Neville says keeping De Gea would be best business the club can do .
  Gareth Bale and De Gea swap? Pair will likely be Real Madrid team-mates .
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