Wayne Rooney
Rooney had handed in an official transfer request in 2010Reuters

Manchester United owners were fearful that they would be losing their striker Wayne Rooney to rivals Manchester City when he handed in an official transfer request in 2010.

Tehsin Nayani, the former spokesman of the Glazer family, has revealed in his new book, "The Glazer Gatekeeper", that there was "a growing resignation among the club's hierarchy" that the former Everton striker was "on his way to join Abu Dhabi-owned Manchester City".

Rooney has had his fair share of problems at Old Trafford and in 2010, his United future was at the height of uncertainty when he handed in a transfer request after falling out with the then United manager Sir Alex Ferguson.

The 29-year-old striker was reportedly disappointed with United's ambition during that time, especially after the departures of Cristiano Ronaldo and Carlos Tevez to Real Madrid and Manchester City respectively the previous season.

Although the Red Devils spent £43 million on the transfers of Antonio Valencia, Gabriel Obertan, Mame Biram Diouf, Chris Smalling, Javier Hernandez, Bebe and Michael Owen (free transfer), Rooney felt that they did not do enough to strengthen the squad.

Ferguson revealed in his autobiography that he had spoken to the Rooney and striker had questioned him why he had failed to sign Werder Bremen's Mesut Ozil (currently at Arsenal), who had opted to join Jose Mourinho's Real Madrid for around £12 million after having enjoyed an excellent 2010 World Cup with Germany.

"Wayne said that we should have pursued Mesut Özil. My reply was that it was none of his business who we should have gone for," Ferguson wrote in his autobiography, which was published in 2013. "I told him it was his job to play and perform. My job was to pick the correct teams."

Things eventually settled and England striker ended up signing a new five-year contract worth a reported £2,00,000 a week at Old Trafford.

After the whole saga, Rooney claimed he had never considered joining the Citizens, insisting that he would have played somewhere abroad if he had left United.

"Everyone is saying that I was definitely going to Manchester City. Believe me, if I had gone, it wouldn't have been in England, I'd have gone abroad," he had told MUTV in 2010.