It's hard to remember a transfer that collapsed quite as spectacularly as David De Gea's this summer.

Real Madrid's interest in the Spain international had been well-documented for the best part of a year, but it appears they only entered negotiations with Manchester United on the final day of the La Liga transfer window which, it turns out, wasn't enough time for both clubs to get all their paperwork in before the 11pm deadline.

Of course, Real Madrid blame United and United blame Real Madrid for the deal falling apart at literally the final hour, but it remains to be seen what will happen to the 24 year-old whose long-awaited move failed to materialise.

Indeed, with his contract set to expire at the end of the season, the Red Devils will be left in a sticky situation if the 6 foot 4 shot-stopper decides against penning a new deal.

They might be forced to sell him in January rather than lose him for free in the summer, meaning they'll require an immediate replacement.

But fear not United fans, for Football Fancast is here to help. Using our god-given powers of transfer know-how, we've listed FIVE such replacements the Red Devils could snap up in the new year.

JASPER CILLESSEN

Netherlands No.1 Jasper Cillessen flourished under Louis van Gaal's leadership at last summer's World Cup, which is more than enough to make you a Manchester United target nowadays.



To give credit where it's due, the 26 year-old was also in fine form for Ajax last season, claiming the club's Player of the Year award for his 63 saves and Eredivisie-best twelve clean sheets in 32 appearances.



The Red Devils' expected bid for the 6 foot 2 shot-stopper never arrived during the summer, despite plenty of reports alleging an offer around the £20million mark throughout the transfer window, but we could see LVG return for his former No.1 once De Gea has officially departed from Old Trafford.



Furthermore, the Dutch outfit probably won't be too miffed about selling; Cillessen is understudied by the more than capable Diederik Boer, who made almost 300 league appearances for PEC Zwolle before moving to the Amsterdam Arena in 2014.

FRASER FORSTER

A lightening quick shot-stopper blessed with an aerially dominant and seemingly impenetrable 6 foot 7 frame, Southampton's Fraser Forster is emerging as real contender for Joe Hart's No.1 jersey within the England fold.



The 27 year-old was nothing short of phenomenal during his debut campaign with the Saints last term, claiming the second-most clean sheets of any Premier League goalkeeper, 13 in 30 outings, despite having his season ended early through injury.



Also boasting considerable experience in the Champions League from his time with Celtic - where the former Newcastle United youngster gained huge notoriety for a spate of talismanic displays against Barcelona - in my opinion, Forster's ready to represent one of the Premier League's top clubs.



Whether the Saints are ready to sell is another issue. But they did sign former Roma No.1 Maarten Stekelenburg on loan during the summer as cover for Forster amid his lengthy injury lay-off, so they won't be left shorthanded.



That being said, it remains to be seen if the England international will have recovered from his broken kneecap by the time the transfer window reopens in January.

KEYLOR NAVAS

Having been included in the £29million David De Gea deal that eventually never happened, one can only assume Manchester United would be fairly comfortable with Keylor Navas as their long-term No.1.



The 28 year-old hasn't been tested much at the Bernabeu since arriving for €10million last summer, managing only eleven appearances across all competitions last term as Iker Casillas hang onto the No.1 jersey for dear life.



But Navas is well proven from his prior exploits in La Liga with Levante, rather incredibly making the most saves of any keeper in the division, a whopping 141, and keeping the second-most clean sheets, 17 from 37 outings, during the 2013/14 season.



He also stood out for Costa Rica at the World Cup in Brazil, helping his country reach the tournament's quarter-finals with three clean sheets in five appearances and a Man of the Match display against Greece in the Round of 16.



Navas is believed to have agreed personal terms with United at some point during the De Gea debacle. But whether Los Blancos are still interested in doing business with the Old Trafford outfit - and vice versa - remains to be seen.

BERND LENO

A suggestion from slightly further afield, Bayer Leverkusen's Bernd Leno hasn't been directly linked with United but a combination of impressive form and the Red Devils' need for a new No.1 could soon change all that.



Indeed, the Germans seem to produce top-class goalkeepers on a never-ending conveyor belt and the 23 year-old is one of the latest to emerge from the production line, last season recording the second-most clean sheets of any 'keeper in the Bundesliga, an impressive 16, after Bayern Munich's Manuel Neuer.



Furthermore, the Germany U21's been first choice at the BayArena since 2011, when he was just 19 years of age, and in that time has made 31 appearances in European competitions - so for such a young No.1 he's already got plenty of experience.



Under contract until 2018, Bayer will feel under no obligation to cash in on Leno, especially half way through the season. But with two international goalkeepers also on their books - albeit one-cappers for the USA and Croatia - they can probably afford to let him go at the right price.

HUGO LLORIS

An equally quick goalkeeper of similar shot-stopping prowess and easily the best No.1 outside of the Champions League, Hugo Lloris has always felt like the natural successor to David De Gea.



Indeed, he's continually demonstrated top class ability since moving to White Hart Lane in summer 2012, last term completing the most saves of any goalie in the Prem's top six, a whopping 89, whilst keeping eight clean sheets behind an incredibly porous Spurs defence.



Lloris has never hidden his desires to play in Europe's top tournament, seeing it as vital to maintaining his captaincy within the France fold.



The obvious problem, however, is Tottenham's ability to drive a hard bargain - or more particularly Daniel Levy's. Despite being safeguarded from the 28 year-old's departure for some time through understudy and former Swansea City No.1 Michel Vorm, the Lilywhites chairman will attempt to squeeze every penny out of the Red Devils - especially if he's to sell Lloris mid-season.