Manchester United are being linked with Schalke goalkeeper Alexander Nubel.
Off contract in June, Nubel - at 23 - is regarded among the best young shot-stoppers in Europe.
BILD says United are watching Nubel, along with PSG, Bayern Munich and Roma.
Schalke management are growing concerned they face losing their No1 for nothing in June.
A January sale for Nubel cannot be ruled out.