Schalke captain Marcelo Bordon fears they could lose goalkeeper Manuel Neuer, a Manchester United target.
The 23-year-old is reportedly attracting interest from Bayern Munich and Manchester United and Schalke's worrying financial plight may force them into a sale this winter.
And Bordon thinks Neuer should be sold in the interests of his club.
"The financial aspect plays a role and maybe it would be better in that sense if he were to leave because we could get a hell of a lot of money for him," Bordon told the Bild newspaper.