Borussia Dortmund's Juergen Klopp has crafted a reputation as one of Europe's ablest managers.
Yet even he could have been forgiven for throwing his hands up in resignation when, two days before the biggest game of his life, news leaked that Dortmund were selling their star player to their biggest rivals.
Bayern Munich, Bundesliga winners and fellow Champions League semi-finalists, had paid Mario Goetze's €37 million (£32m) release clause to bring him Bavaria.
At 20, Goetze's potential appears limitless; already one of Europe's best attacking midfielders and a regular in the German national team, with a decade of improvement ahead.
And yet to Dortmund fans he represents more than just a brilliant player. He joined the club aged eight. He came through the ranks. He publicly said he would not leave. He was their man. And now he has gone.
Except he hasn't yet. Goetze must play out the rest of the season in supremely awkward circumstances.
Less than 48 hours after the news emerged - the timing either unfortunate or mischievous, depending on who you believe - Dortmund play Real Madrid in the Champions League last four.
There is no question of Klopp taking Goetze out of the line of fire - he can only try to quell a firestorm of anger from Dortmund supporters burning with betrayal.
The fans must contain their fury and roar Goetze on, because it is hard to imagine a Dortmund win without him near the top of his game. And these opportunities come along seldom.
But how can they voice full-throated support for the man who 12 months ago said: "Everyone knows how comfortable I feel in Dortmund. The club are far from finished with their recent resurgence. And I want to be part of this development."
Klopp said on Tuesday: "For everybody who is angry, all I can say is that, a year ago, we signed Marco Reus from Moenchengladbach and they hardly broke out in celebration there, but he still played some excellent games for Gladbach.
"We will do all we can to ensure our concentration is not disturbed. When you deal with things in life in the right way, then you can draw energy from them."
You can count on plenty of energy when Goetze runs out at Dortmund's Signal Iduna Park - much of it negative judging by the initial reaction.
Football fans are very good at joining the dots - and Bayern legend-turned-pundit Lothar Matthaeus was happy to hand them a felt-tip pen.
When Klopp revealed the deal was done just after Dortmund's narrow Champions League win over Malaga, Matthaeus suggested his form had already been affected.
He said: "Goetze was a decisive player and wasted six or seven big chances. He showed nerves then and this whole thing has certainly been developing for a while."
That Bayern have snaffled another fine player from a rival should come as no surprise - only the timing.
Their modus operandi has long been to strengthen themselves as they weaken their rivals. Goetze's arrival achieves both aims.
In the last 20 years, Bayern have captured prize assets from Leverkusen (Lucio, Michael Ballack, Ze Roberto), Karlsruhe (Oliver Kahn, Mehmet Scholl), Werder Bremen (Miroslav Klose), Stuttgart (Mario Gomez, Giovane Elber) and Schalke (Manuel Neuer) among others.
Despite the historical precedent, Dortmund do not feel like a feeder club. They have won the last two Bundesliga titles. They, too, are in the last four of the Champions League. They boast a stadium bigger than Bayern's Allianz Arena in the 80,000-capacity Signal Iduna Park.
They are a formidable club - but to lose Goetze is a kidney punch, a stark reminder that Bayern's superior financial clout normally wins out.
Bayern know how to disrupt a rival. This time - knowingly or otherwise - they have surpassed themselves.
- Sports & Recreation
- Borussia Dortmund