Manchester City made a huge mistake selling Nigel de Jong in 2012

Sneijder, Robben and De Jong Netherlands

Manchester City have had problems protecting the back four - do they miss Nigel de Jong?

Manchester City had two morale boosting wins over Swansea City and Bayern Munich in recent days, but one big problem continues to cause issues for Manuel Pellegrini.

City have struggled to protect the back four all season, with both Fernando and Fernandinho failing to cover for the deteriorating Yaya Toure in midfield.

It's left City woefully exposed, especially with a raw rookie centre back like Eliaquim Mangala thrust into the first team early on in the season.

What's strange though, is that City have actually sold a number of players who fill the exact role that they are missing right now.

In recent months, the Blues have let Gareth Barry and Javi Garcia leave the club for Everton and Zenit St. Petersburg, but now they lack an impact defensive midfielder given Fernando's average displays.

Yet one particular exit stands out from the others - Nigel de Jong.

The Dutch destroyer was a key part of City's title winning side, shielding the back four and forming a sensational midfield partnership with Toure in the process.

With 137 appearances to his name, de Jong was a mainstay during City's recent successes, but just months after that dramatic title win on the final day of the 2011-12 season, de Jong was sold for £3.5m to AC Milan.

Giving up a player like de Jong for such a pittance was a huge error of judgement from City and then-manager Roberto Mancini, and you have to wonder what Pellegrini would give to have him back at the Etihad Stadium now.

The 29-year-old's contract at Milan expires at the end of this season, and whilst City could be able to bring him back on a free transfer, a more likely destination would be their bitter rivals Manchester United.

De Jong played a starring role for Louis van Gaal's Netherlands at the World Cup this summer, proving that he can still perform at the very highest level - and a reunion at Old Trafford could be on the cards in January, if recent reports are to be believed.

City desperately need to bring in a top class defensive midfielder - and it must hurt to know that they had one of the best, but let him go for a cut-price fee.

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