The Spanish number one has less than 18 months left to run on his current deal with the 20-time English champions to raise question marks about his future.
Manchester United activated a clause in his contract in December that extended the Spain international’s stay by an additional 12 months until the summer of 2020.
However, the Red Devils have been left in an increasingly dangerous position where De Gea could refuse to sign a new contract and leave the club for nothing at the end of the 2019-20 Premier League season.
Reports in the British media suggest that De Gea is seeking to equal Alexis Sanchez’s lavish wages at Manchester United, which are thought to be in the region of £350,000 a week.
Now, former Manchester United midfielder Kanchelskis has been keen to stress the importance of keeping De Gea at Old Trafford.
“There is a worrying situation developing with De Gea at Manchester United,” Kanchelskis told bWIN.
“He still hasn’t signed a new contract and the club will soon be faced with a decision either to sell him for a fee this summer or risk allowing him to leave for a free.
Kanchelskis added: “De Gea is the best goalkeeper in the world so it would be a nightmare if he doesn’t sign a new contract at Manchester United.
“It’s bad enough that he may be leaving the club, but it would be an even bigger travesty if they were to let it happen on a free transfer.”
Sir Alex Ferguson signed De Gea in a £17m deal from Spanish side Atletico Madrid in the 2011 summer transfer window.
De Gea was recruited to replace Edwin van der Sar at the 20-time English champions.
After a slow start, the Spanish shot-stopper established himself as one of the best goalkeepers in the world.
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