David De Gea
De Gea is currently in excellent form at Manchester UnitedReuters

Manchester United have not been able to convince their goalkeeper David De Gea to extend his contract at Old Trafford this season, but some YouTube pranksters managed to get the Spaniard into signing a new deal presented by them, after the Reds Devils' 1-1 draw against Arsenal on Sunday.

The 24-year-old goalkeeper, who completed a £17.8 million switch from Atletico Madrid to Manchester United in the summer of 2011, has been in excellent form this season and, as a result, the Red Devils are keen to extend his contract, which runs out in 2016.

However, it appears that the Spaniard is going to leave Old Trafford this summer as he has still not signed a new contract despite the Red Devils reportedly offering him a bumper deal worth a reported £200,000-a-week.

De Gea has been heavily linked with a move back to Spain, with Real Madrid targeting him to replace their ageing goalkeeper Iker Casillas.

But it looks like some YouTube pranksters, who are also Manchester United fans, have finally managed to do what United have been trying all season -- getting De Gea to sign a new deal.

The pranksters were waiting outside Old Trafford after United's 1-1 draw against Arsenal, before asking De Gea to sign autographs.

When De Gea walked up to them, they gave him a piece of paper which the Spaniard immediately signed.

Little did he know that the paper was in fact a contract that said that he would be remaining at the club for ten years unless United failed to qualify for the Champions League for two seasons in a row.

"I, David De Gea agree to sign a new contract for Manchester United Football Club for ten years unless Manchester United fail to play in the Champions League for two seasons running," read the contract, according to the Daily Express.

This little trick may not be enough to convince De Gea to stay at Old Trafford beyond this season, but the United fans can now say that they at least tried.