Ruud van Nistelrooy's agent has revealed that the striker is unhappy with Hamburg after they refused to let him re-join Real Madrid.

GettyImagesRuud van Nistelrooy has represented Manchester United and Real Madrid

• Veh: Van Nistelrooy is staying
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Real are keen to bring in a striker this January to give them cover up front after Gonzalo Higuain was ruled out for four months, and Van Nistelrooy admitted that the prospect of returning to the Bernabeu was tempting.

However, Hamburg would not sanction a deal for the 34-year-old Dutchman and Van Nistelrooy's agent has now claimed that his client will not sign a new deal in Germany.

"A contract extension with Hamburg can now be ruled out," Rodger Linse told the Hamburger Morgenpost. "He cannot understand it [why Hamburg did not let him go] and he has got a problem with it. It is very, very painful. It is sad because Hamburg have no idea what they are doing to Ruud with this decision."

Van Nistelrooy scored 46 goals in 68 games during a three-and-a-half-year spell at Real after joining from Manchester United and has already bagged six goals this season for Hamburg.