For two years now, Real Madrid have been interested in raiding Manchester United for De Gea's services.
The Spain international came close to sealing a move to the Bernabeu in 2015, only for paperwork problems to ensure he remained at Old Trafford.
Despite being exiled by Louis van Gaal, De Gea remained at the club and has helped them win three major trophies in the last 13 months – under both the Dutchman and his successor Jose Mourinho.
As a result, the Red Devils are keen to stop him moving to Real, who are determined to land their man at long last.
David De Gea transfer: Potential replacements for the Man Utd keeper Thu, June 1, 2017
Click to reveal the stars linked with replacing David de Gea at Man Utd
Play slideshow Getty Images 1 of 9
Real Madrid are desperate to lure David De Gea away from Manchester United
David De Gea is a very good keeper but he is at Manchester United
Ronaldo was the last player to swap Manchester for Madrid, moving in the summer of 2009 for a then world-record fee of £80million.
But the 32-year-old, who will appear in a fifth Champions League final of his career against Juventus this evening, has refused to add to the growing talk that the goalkeeper could make the move.
“Keylor Navas is Real Madrid’s goalkeeper," he said.
Get Quotes on Home Insurance
“De Gea is a very good keeper but he is at United. They talk about 50,000 footballers every year and they are always the same.
Real Madrid star Cristiano Ronaldo has insisted that Keylor Navas is the club's goalkeeper
“Of the players they talk about, maybe one or two will arrive and that’s it.”
United are understood to be making plans in case they do lose the 26-year-old.
Inter Milan goalkeeper Samir Handanovic is on their radar, with the Slovenia 32-year-old establishing himself as one of Serie A's most consistent shotstoppers in recent years.
Real, meanwhile, have been linked with Chelsea's Thibaut Courtois in the event that United manage to retain De Gea for yet another year.