Borussia Dortmund agreed to insert a release clause of €60m in Erling Haaland's contract to seal his signature during the January window.
Haaland was pursued by Manchester United, but made the decision to head to Dortmund instead, where he penned a four-and-a-half year deal.
According to Sky Deutschland, that contract contains a €60m release clause, and Dortmund had to go against club policy and agree to that as it was seen as the only way to get the deal over the line.
In recent years, Dortmund have avoided putting release clauses in the contracts of their players as they have been forced to part ways with some of their most influential names when those fees have been met in the past.
Nuri Şahin's €10m move to Real Madrid in 2011 was the first example, but the most painful was Mario Götze's €37m switch to arch rivals Bayern Munich in 2013. That was the final straw for Dortmund, who made a point out of steering clear of release clauses going forward.
However, they had to agree to grant Haaland the €60m clause as otherwise the transfer 'would not have been possible', with the player's representative - the infamous Mino Raiola - clearly adamant that a release clause was necessary.
It is worth noting that one of the reasons behind United's failure to sign Haaland was Raiola's insistence on inserting a release clause into the contract. The Red Devils weren't happy with the idea of losing him, whereas Dortmund clearly chose to agree to the demands.
Speaking to the Deutschen Presse-Agentur, sporting director Michael Zorc refused to be drawn on the clause, but insisted that Haaland will be a Dortmund player for years to come.
"We never comment on contract details," he said. "Assume that he will play football with us for a lengthy period of time."
Haaland has already featured for Dortmund during friendlies in their mid-season training camp, and he might get the chance to make his official debut when Lucien Favre's side travel to face Augsburg on Saturday.
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