De Gea has enjoyed arguably his finest season in a Man United shirt and is now considered to be one of the best in the world in his position.
The Spaniard has come a long way after joining in 2011 as a skinny youngster and he is now a firm fans’ favourite at Old Trafford.
Van Gaal praised De Gea but revealed he was unconvinced by the 24-year-old early on in the campaign.
Speaking about De Gea, van Gaal said: ”He has made very good development this year because in the beginning I was not so sure of him.
“But now he is fantastic and has saved us a lot of times.”
De Gea is earning a number of plaudits for his displays this season and rightly so.
The player has the potential to become a United legend but he is yet to deny rumours linking him with a move to Real Madrid. De Gea is adored by the United faithful and it would be a huge shame to lose him after the club made him into the keeper he is today.