Hertha Berlin have led the tributes to former player Andreas Biermann following his death at the age of 33.
The defender's latest club, Spandauer Kickers, announced on Saturday that the player had passed away after a long battle with depression.
The club's general manager, Gunter Hagedorn, was quoted by respected German newspaper Bild as saying that Biermann had taken his own life.
Biermann had spoken openly about his battle with depression and subsequent suicide attempts both in his autobiography and on television talk shows in his native Germany, with Kickers revealing in a short statement on their Facebook page: "Our senior player Andreas Biermann has not been able to overcome his depressive illness and died yesterday morning. Our sympathy is with his family."
As German football reacted with shock to the news, Biermann's former club Hertha - where he came through the youth ranks in 1998 before spells with the likes of Union Berlin and St Pauli - expressed sadness at the loss.
In a statement on their official website, Hertha posted: "Some events leave us speechless: Hertha BSC, club management, committees, members and fans are in their thoughts with his family, relatives and friends."
St Pauli paid their own tribute, adding: "Our sympathy goes out [to] his family, we wish you much strength in this difficult time."
The issue of depression in football was brought sharply into focus by the death of former Germany goalkeeper Robert Enke, who committed suicide in 2009 after a long struggle with the illness.
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