Manchester United determined to keep David de Gea from clutches of Real Madrid - despite Victor Valdes move

Louis van Gaal is signing the former Barcelona player on an 18-month deal as back-up - not a replacement

Manchester United are determined to hold onto David de Gea, despite having agreed an 18-month contract with former Barcelona goalkeeper Victor Valdes today.

The club are set to announce that the 32-year-old has signed on at Old Trafford as understudy to De Gea, having been convinced that the former Barcelona goalkeeper – who has not played since sustaining a serious knee injury nine months ago - is not a long-term medical risk.

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But though the decision to sign the Catalonian until 2017 will create doubts about De Gea, who has only 18 months left on his contract, the prospects of Real Madrid bringing the 24-year-old back to Spain this summer are not thought to be substantial. Valdes is considered as a goalkeeper who can provide the kind of genuine competition for De Gea which current No 2 Anders Lindegaard is not offering.

United manager Louis van Gaal has does not consider Lindegaard to be good enough and United had anticipated since the autumn that he would leave Old Trafford this month.

They also seem ready to let third choice Ben Amos leave if another club come in for him. He was criticised by Van Gaal for letting in Miralem Pjanic's 60-yard lob against Roma in pre-season. The only other goalkeeping option is 21-year-old Sam Johnstone, who is on loan at Doncaster Rovers.

Ben Amos will be let go (AP)

United are relaxed about De Gea’s future, after a first half to the 2014/15 campaign in which he has established himself as the top keeper in the Premier League and have been more focused on offloading players in the past month. Anderson is another player United are anxious to get off the payroll and Adnan Januzaj may leave on loan to Paris Saint Germain.

The decision to register Valdes and take him onto the books comes after a two-month analysis of his fitness by United. Their conviction that he does have a future for them will compound the frustration of Liverpool, whose uncertainty led to a reluctance to commit to him. It is thought the Anfield club wanted to take Valdes on trial. Their indifference is thought to have contributed to an uncertainty on his part about a future on Merseyside.

Though De Gea might be seen as a long-term goalkeeper at the Bernabeu, the incumbent Iker Casillas has shown no desire to leave, despite having had to share a first team place in the past few years. He was demoted to the bench by Diego Lopez in La Liga in 2013 but returned to favour with the latter's departure to AC Milan in August. The Costa Rican Keylor Navas, who was signed last summer, is now competing and he will play in the La Liga game against Atletico Madrid on Wednesday night, though there is no sense that signing Spain’s new No 1 keeper from Old Trafford is the club’s priority.

Valdes, who suffered anterior cruciate ligament damage in his knee during a La Liga match for Barcelona against Celta Vigo last March is currently living at the five-star Lowry Hotel in Manchester city centre but it is thought that he is looking for a property.