Borussia Dortmund coach Jurgen Klopp could be forgiven for wearing the look of a haunted man when he leads his team into the Champions League semifinal first leg against Real Madrid on Wednesday night.
The former Mainz boss has witnessed Bayern Munich wrest the Bundesliga title from his grasp with consummate ease this season.
Jupp Heynckes' side currently hold a 20-point advantage over Dortmund and have now been further buoyed by their incredible 4-0 victory over Barcelona in their semifinal first leg.
However, while Bayern have strolled to success this season, Klopp and the supporters will recognise that an even greater threat to their hopes of a third league title in four years awaits.
It was a devastating blow just before the club's biggest match since the 1997 semifinal against Manchester United.
The Westfalenstadion side went on to win the trophy that season, but years of financial struggle would follow with the club twice on the verge of bankruptcy in 2003 when a loan from Bayern secured their future (Goal.com) and 2005 (BBC News).
Few could argue with Dortmund being wary of history repeating itself and the sale of Gotze makes economic sense.
For Klopp and the supporters, though, it was a potentially destructive blow ahead of the meeting with Jose Mourinho's La Liga giants.
The Dortmund boss failed to disguise his feelings at the timing of the announcement during his pre-match press conference yesterday (The Guardian).
I've known about it since a day after the Malaga game. Now I can say that time heals everything. It's going to take a while, this news is not good for us. The timing of it is not ideal. Anybody can make their own minds up as to why it's come out now, but it is out
Gotze, 20, has been an outstanding figure for Dortmund, but his profligacy in front of goal in the quarterfinal against Malaga almost cost the German side dearly.
Klopp look set to keep faith with the midfielder for tonight's home leg against Real, but Gotze is facing the genuine possibility of hostility from many Dortmund supporters.
The Metro reported that replica shirts featuring Gotze's name had been burnt and even Bayern legend Lothar Matthaus claims the Westfalenstadion fans will feel "betrayed" by Gotze's move (Daily Express).
This should have been an historic week for Dortmund and Klopp. Instead, there is a danger that Gotze's move will trigger something less memorable.
However, while Gotze's departure on July 1 has now been sealed, the Dortmund coach will also have other considerations for the future.
According to the Daily Telegraph, Lewandowski is waiting to hear Manchester United's striking intentions before joining the club, although the ominous presence of Bayern and Pep Guardiola are waiting in the wings.
Central defender Hummels has already voiced his interest in joining Barcelona this summer (Bild via Sky Sports).
The 24-year-old is set to return to the team on Wednesday night after a month out with an ankle ligament injury, but this is set to be the Germany international's final run-in with Dortmund.
Hummels, Gotze and Lewandowski are the spine of the current Dortmund team. Losing one might be deemed frustrating, but losing three will be a nightmare for the manager.
Klopp has called for support from the terraces against Madrid, notably in the case of Gotze, but his departing players also owe him for providing the platform for their careers.
Would there be any better way of repaying him than to produce the game of their lives against Real?