The Red Devils shot stopper has been heavily linked with a move to Los Blancos throughout the Premier League season after a string of impressive performances for his club.
I want him to stay. Being selfish, I obviously hope he remains with us
De Gea has just one year remaining on his current United deal, and the Spain international is yet to agree a new contract with the 20-time English champions amid Madrid interest.
United midfielder Mata is desperate for his compatriot to stay at Old Trafford in the long-term, although the former Chelsea man admitted he doesn’t know what decision De Gea will make.
Mata told IBTimes: “I don’t know. To be honest, I don’t know. Ask him because I don’t know. I understand how important he is for us.
“Against Crystal Palace he proved it again with a save that gave us the three points.
“I want him to stay. Being selfish, I obviously hope he remains with us. He gives us many points.”
De Gea won the Premier League title in 2013 after the goalkeeper joined United in a £18m deal from Atletico Madrid in 2011.
The former Los Rojiblancos man has made 158 appearances for United during his four-year stay at the Manchester club.
The United shot stopper was named in the PFA team of the year, although he lost out on the PFA player of the year award to Eden Hazard.
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