The 23-year-old Italian midfielder was heavily linked with a move to the Giallorossi last summer but a deal failed to materialise, leaving him in Reggio-Emilia with the Neroverdi.
Frattesi has continued to impress this season with Sassuolo and now seems destined to be sold in the upcoming summer transfer market, ready to take the next step in his career.
Roma have maintained interest in the midfielder and Juventus recently opened talks with the Neroverdi to discuss a deal.
As reported by La Gazzetta dello Sport, Manchester United have started following Frattesi closely and even sent scouts to observe him in Sassuolo’s recent matches.
The Red Devils started keeping tabs on the 23-year-old midfielder in the first half of this season and are still keeping a close eye on him, possibly preparing for a move in the summer.