David de Gea
De Gea has been in startling form for United this season Getty Images

Manchester United are running the risk of losing David de Gea on a free next term after failing to convince the player to sign a new contract with the Red Devils, according to the Daily Mirror.

The Spaniard, whose contract expires in 2016, is yet to commit his future at Old Trafford, which given the circumstances has left United in a state of limbo, especially if they fail to make the Champions League next year. De Gea has been their best player thus far this season, single-handedly winning games for Louis van Gaal after being left exposed by his defence.

His barrage of saves earlier in the season against Arsenal at the Emirates allowed United to sneak in a couple of goals at the other end and extend their lead in the top four and also kept the Red Devils in the game against Everton when they were on the hilt and ready to capitulate.

His departure would be a major blow for the Dutchman, who is planning yet another major spend this summer to revamp his squad after a plethora of players he bought last summer have failed to impress.

Valued at £50m ($74m), De Gea is among the most sought after goalkeepers in Europe and will not have a dearth of interest should United fail to tie him down to a contract before the summer. Moreover, given that he is in the final year of his contract, his value may dip considerably with clubs willing to sign him on a free next year.

Real Madrid are believed to be frontrunners for his signature and may make a bid in the summer to test waters.

An insider at United told Mirror, "It has turned into the worst-case scenario. There has been no indication that De Gea will sign a new contact and at some point a decision will have to be made when to cash in on him.

"When a player enters the final 12 to 18 months of his contract, his value begins to drop dramatically.

"There's talk of De Gea being worth £50million, but that is unrealistic given there is probably only one club he would sign for," he concluded.