Manchester United get green light to pursue Borussia Dortmund striker Robert Lewandowski But with Lewandowski rejecting Dortmund's attempts to extend his current contract, which expires in June 2014, Borussia chief executive Hans-Joachim Watzke has admitted that a decision will be made on his future at the end of the season. It's a decision we will have to take and it's our decision. It's not something to be decided by others. As often as I am talking to Robert, I do not have the impression he wants to leave us. Lewandowski, who has scored 39 goals in 82 league games for Dortmund, is understood to have told the club that he will not sign a new contract and that he is keen to follow former team-mate Shinji Kagawa to the Premier League, with United his favoured destination. Dortmund coach Jurgen Klopp insisted last week that Lewandowski would not be allowed to leave in January, with the club determined to keep their team together in an effort to win a second Champions League title this season. Meanwhile, Wayne Rooney is expected to be fit for Saturday's clash with Sunderland at Old Trafford despite being affected by a virus this week.