The 19-year old striker, who scored twice in the Red Devils' 4-1 pre-season friendly win over New England Revolution on Wednesday, spent the second half of last season on loan with Sampdoria but admitted that he could not wait to get back to Old Trafford.
He now hopes he can become a regular fixture at a club he feels nobody else can compare to.
"I'm very happy because I had a difficult six months last season, so it's good to start well this season," he Sky Sports News.
"I couldn't wait to get back here when I was in Italy, even though it's my country.
"Nothing can compare to Manchester United, so I'm really happy to get back here, and I hope to stay."