Sassuolo will reportedly demand a fee of €20million for highly-rated midfielder Alfred Duncan.
The Ghana international is a target for several clubs including AC Milan, who are keen on improving their squad ahead of next term after another trophyless season.
Milan’s interest in Duncan has reportedly been approved by coach Gattuso.
But Sassuolo have issued a hands-off warning.
According to reports in Italy, the Black and Greens will only consider a huge offer.
Should the midfielder be prised from Mapei stadium, the fee would represent a great profit on the €6m Sassuolo spent to sign him from Sampdoria in 2016.
Duncan has made a total of 25 appearances this season.