By Jamie Sanderson

Manchester United have expressed an interest in Borussia Dortmund striker Robert Lewandowski, after talks over a new contract broke down, according to the players agent.

Man United 'interested' in Borussia Dortmund's Robert Lewandowski

Lewandowski is currently enjoying his most prolific season to date, having scored 30 times in 46 matches this term, including three in the German Cup final on Saturday, as Dortmund completed the league and cup double with a 5-3 win over Bayern Munich.

However, despite Dortmund’s success on the pitch, they are struggling off it, with a host of top players failing to agree new contracts, including 23-year-old Lewandowski, who was watched by Manchester United manager Sir Alex Ferguson and his assistant Mike Phelan during the clash in Berlin this weekend.

United were also there to make checks on another Dortmund contract rebel – winger Shinji Kagawa – and German powerhouse Mats Hummels, both of whom also scored, but speaking after the game, Lewandowski’s agent Maik Barthel was quick to talk up the Red Devils main interest being in his client:

‘I can confirm that the new contract offer of Borussia Dortmund is insufficient. I am also able to confirm an interest of Manchester United in the services of Robert Lewandowski,’ Barthel told Bild.

United are thought to be long-term admirers in Lewandowski, while Chelsea and Liverpool have previously scouted the player, along with Inter Milan and Juventus, but Dortmund have always maintained they will not part with their leading marksman this summer.

Yet with the contract dispute showing no signs of resolving itself, a deal could be in the offing, especially if United firm up their interest with a strong bid, or allow want-a-away forward Dimitar Berbatov to return to Germany as part of the deal.

A fast, instinctive striker who is excellent in the air, Lewandowski is likely to cost in excess of £15 million.