BORUSSIA DORTMUND CEO Hans-Joachim Watzke admits they face a big challenge to keep Erling Haaland.
The Norwegian striker has scored an incredible 68 goals in 67 matches for the Bundesliga club since his arrival from RB Salzburg in January 2020.
That phenomenal record has made the 21-year-old one of the hottest properties in Europe with a host of big guns chasing his signature.
Real Madrid and Barcelona have both been linked while Manchester United remain keen on bringing him to Old Trafford.
Chelsea were also in the running for the hotshot before they switched their focus to bringing back Romelu Lukaku instead.
Despite holding on to their star man in the summer window, Dortmund are believed to have an agreement with Haaland that he has a release clause between £75million and £100m that can be activated at the end of this season.
And even though he did not confirm that, Watzke did admit it will be a struggle to hang on to the forward.
He told : “Of course it will be difficult. I am not saying, however, that it is completely out of the question.
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“We'll do everything we can to keep our top players loyal to us in the future.”
England international Jude Bellingham, 18, is another now catching the eye at Dortmund.
Boss Marco Rose was recently quizzed on the possibility of keeping both, which replied: “The two boys are currently players with us.
“We are happy to have them and anything else is just rumours. In the summer, we will see how it goes for both players.
“But I will do everything to ensure they stay. Tie them down (to new contracts)? No idea (what the future holds), let's see.”
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