The Royal Blues announced in the aftermath of their 1-1 round of 16 draw at the Turk Telecom Arena that they would contact UEFA over whether the Cote d'Ivoire forward was properly registered to feature on Wednesday.
Galatasaray official Bulent Tulun has hit back, insisting the Istanbul giant is innocent of any wrongdoing and that Schalke is deliberately trying to start fires ahead of the return leg in Gelsenkirchen.
"Everything is fine with Drogba," Tulun told Bild. "Schalke are just trying to provoke us. What is this nonsense?"
Meanwhile, Tulun's German counterpart, Horst Heldt, confirmed his intention to seek clarification over the matter.
"We have discussed this with our lawyers intensively," Heldt said. "Not protesting at all would be negligent towards the club. We are not trying to obtain something by fraud. We only want legal certainty."
Drogba joined Galatasaray on an 18-month contract in the January transfer window after he chose to end his Chinese adventure with Shanghai Shenhua amid reports that the club failed to pay his wages.