Sinkgraven’s form has convinced Heerenveen pal De Roon that he will make a big-money move next summer.
“He is so nimble, he almost dances on the field,” De Roon told Dutch publication Voetbal Primeur.
Sinkgraven recently told the same publication that he is flattered by the mounting interest in him.
He said: “It is a compliment that there are so many clubs interested in me.
“Whether it is all true, we will then see again.”