Kehl believes it's impossible for Dortmund to catch Bayern

Robert Lewandowski is considering hiring personal security for the last few months of his Borussia Dortmund contract.

It was revealed last Saturday that Lewandowski, 25, had agreed to join Bayern Munich at the end of the season on a free transfer, after agreeing a five-year deal.

Now, that the long-running Lewandowski transfer saga has finally come to an end, the striker is believed to be fearing for his safety having risked the wrath of angry Dortmund fans.

"Yes, we are seriously considering it," Maik Barthel, one of Lewandowski's agents, was quoted as telling Bild.

Since the announcement of his switch to Bayern, Dortmund supporters have shown ill will towards Lewandowski on social networks. In 2012, unknown perpetrators broke into Lewandowski's house in a small city close to Dortmund.

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