'Big opportunity' for Dortmund to rise has been dampened by news of the lead man's impending departure, but coach Klopp is confident perspective will prevail.
Champions League: Mario Goetze will go but Dortmund confident storm shall pass
Jurgen Klopp, Borussia Dortmund's head coach, heard about the leak at 10pm on Monday night. Until then, it had been a secret known to him, to his star player, some leading executives from his club's major domestic rivals and to few others.
Once Klopp found out Germany's best-selling newspaper had the story that Mario Goetze, emblem of Dortmund's recent renaissance and icon of German football, would be leaving in the summer, to join Bayern Munich, he wondered if the timing of the revelations could be any more damaging.
Bild-Zeitung published yesterday morning, specifying that Bayern had agreed to pay the €37 million (Dh177.6m) release clause in Goetze's Dortmund contract - which runs until 2016 - to make him one of theirs next season.
Suddenly, in the midst of two eagerly anticipated Uefa Champions League semi-finals, with Bayern in action against Barcelona last night, and Dortmund hosting Real Madrid today, the fiercest rivalry of the Bundesliga had taken on qualities usually associated with the obsessive tensions between Spanish football's most famous enemies.
Goetze's move has echoes of some of the sport's most contentious transfers.
Rather like Luis Figo's turn-of-the-century turncoat episode, when the Portuguese winger, loved at Barcelona, absconded to Madrid, it has ignited fury among Dortmund supporters.
Some of them are suspicious at the way Bild, a paper well connected at Bayern, found themselves with the details less than 48 hours before Dortmund's biggest match in 15 years, and printed the story on the day Bayern faced Barcelona.
Klopp hinted at his own suspicions when he said yesterday: "Whoever might have wanted to disrupt our preparations for the Madrid match, will not succeed."
He did, though, concede his concerns at the reception which Goetze, an essential player in Dortmund's zestful attacking, their creative imagination, might hear from many among the 70,000 in the Westfalen stadium.
"We have too a big an opportunity as a club right now to be showing discontent about something," he said.
"I hope fans will use the time leading up to the game to put everything into perspective."
Klopp offered his own perspective. While Dortmund, who Goetze helped to the Bundesliga titles of 2011 and 2012 before watching Bayern run away with this season's title - had widespread sympathy elsewhere in German football because of the Munich club's notoriously predatory character in the domestic transfer market - Klopp pointed out that in the modern game, ruthlessness is not exclusive to Germany's biggest club.
"A year ago, we captured Marco Reus for another big sum in the transfer market," said the Dortmund head coach. "The club we took him from, Borussia Monchengladbach, weren't exactly dancing for joy."
Nor, indeed, were Bayern. The snatching of Goetze is backgrounded in two years of Bayern's chasing in Dortmund's slipstream in domestic football and the frustration felt in Munich when Reus - so often spoken of in tandem with Goetze, as nimble, talented players in the vanguard of a skilled generation of young Germans - chose to join Dortmund rather than Bayern.
Goetze, a native Bavarian, has now done the opposite.
Klopp, loyal to a player who has grown in stature under him and who he wants to see perform confidently tonight, explained Goetze's decision. "He hasn't fallen out with anybody here," said Klopp.
"Mario simply saw a chance from next season to work with an extraordinarily successful head coach.
Pep Guardiola, once of Barcelona, has signed to coach Bayern next season. Klopp then made joke at his own expense.
He was not Guardiola: "I would like to have gone further with Mario, but I can't make myself 15cms shorter and start speaking Spanish. I will stay where I am … I think."
Dortmund followers, certainly, would not like to lose another star, and Klopp is one.
Intense, dynamic and sure of himself, the coach has an extra task ahead of tonight's formidable challenge against Jose Mourinho's Madrid, and that is to focus on Goetze and the positive energy of one of Europe's most vociferous crowds.
But at a club who were close to bankruptcy less than 10 years ago, an ill-timed transfer blow is only a relative crisis.
"I have been here long enough to know," said Klopp, "that our fans have been in extreme situations before and they understand how to support us all."