With Norway international Haaland almost certain to leave the Westfalonstadion this summer, in what may end up a bidding war, Dortmund have been investigating potential options.
Kalajdzic, a 23-year-old Serbian striker who has 14 goals in 28 games this season, is seen as a primary target. Stuttgart will be well aware of Dortmund’s need should Haaland go, though, and could well have a bidding war of their own.
West Ham are one of a few Premier League clubs known to be interested, while RB Leipzig are also monitoring the situation.
David Moyes wants to bolster his attacking options after a season that has seen West Ham defy expectations, even amid stretched resources up front.
Finances could be an issue if the club fail to make Europe, though, and West Ham have been investigating the possibility of a loan before purchase.
Given Kalajdzic’s popularity, a full sale looks far more likely, with Dortmund currently in the strongest position.