Following his £18.9m move from Atlético Madrid in summer 2011, De Gea has come through a difficult start at the club that featured blunders and questions over whether he had the physique to deal with the Premier League's uncompromising nature.
But after emerging in the second half of last season as an integral member of the title-winning side and being voted in the Premier League team of the year, De Gea has established himself as one of Europe's finest goalkeepers.
"I actually enjoy the physical side of it all now," he said, speaking on United's pre-season tour. "I knew I had to become bigger physically. You can see I look different to when I first came here I have much more muscle. I have worked hard in the gym lifting heavy weights and doing a lot of exercises. It was a very intense regime. I changed my diet as well and now I eat an awful lot more than I used to when I came here to build myself up for the physical challenges of the English game."
The United squad would bombard De Gea with aerial deliveries and practise crowding him. "In training the players would deliberately hit high balls into me and barge into me so I would get used to that side of the English game," he said.
De Gea was 19 when he joined, and points to how he had to not only adjust to the glare of being United's No1 but also moving to a new country. "Being the Manchester United goalkeeper is one of the most difficult jobs in football when you look at the size of the club and the goalkeepers who have been here before. There is a lot of pressure on you but I have worked hard to cope with that.
"I do not think people appreciate just how hard it was for me coming to a new country at that age and a different type of football. My immediate family came over with me from the start but I missed my friends back home.
De Gea's nadir seemed to arrive last January when a last-minute error allowed Tottenham Hotspur to grab a 1-1 draw at White Hart Lane. The Spaniard weakly punched a Benoît Assou-Ekotto cross, allowing Aaron Lennon to set up Clint Dempsey, who equalised deep in added time. This caused Nemanja Vidic, Patrice Evra and Danny Welbeck to stare intently at him in an incident highlighted on Sky TV by Gary Neville, the former United captain.
However, De Ge believes that was a blip. "I look at that Tottenham game and I still think it was a great game even though I made a mistake at the end," he said.
Now, he wants to become one of United's greats, with Spain's first-choice keeper, Iker Casillas, stating recently he is his natural successor. "It is great that a goalkeeper as good as Iker has said that I could be the best of them all. When Edwin van der Sar said he was leaving Manchester United [two years ago] I wanted to be the man to replace him. I would love if one day the fans speak of me in the same way they speak of Edwin and Peter Schmeichel. That would mean all the hard work has paid off."
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image: © James Boyes