Borussia Dortmund have confirmed that one fan passed away during the 2-0 win over Mainz 05, which prompted an emotional rendition of club anthem 'You'll Never Walk Alone'.
The 81,000-capacity Westfalenstadion fell into silence once news of the death spread through the stands.
It was thought at the time that a second supporter had lost his life, but it has now been revealed that the spectator in question was resuscitated at the scene and is in a stable condition in hospital.
A Dortmund statement released this evening read: "During the game there were two tragic incidents in the stadium in which two spectators had to be resuscitated.
"Unfortunately, one person did not make it and has died. We are full of sadness and the families are in our thoughts. We have received the news from the hospital that the condition of the second person is apparently stable."
Dortmund players stood arm-in-arm at full time in a sign of respect for the deceased fan.