The Gelsenkirchen side have hit out at speculation that the Germany international midfielder could be on his way to the Allianz Arena in the summer
A Sky Deutschland report on Saturday, shortly before Schalke's match with Hamburg, claimed the Bundesliga champions have struck a deal that will see the highly-rated 22-year-old move to the Allianz Arena at the end of the season.
Heidel, however, is unhappy with the speculation and says that talks over a new contract for the midfielder are ongoing.
"It's not decent for Sky to make an announcement, which is completely baseless, an hour before kick-off," Heidel said.