The 23-year-old is a regular for the Portuguese giants and has already been capped by his international side on the back of his fine domestic showings.
And now it has emerged that United are keen on him, with reports claiming that Louis van Gaal’s side had scouts present to watch him in action earlier this month.
A delegation from Old Trafford are understood to have travelled top Portugal to watch him play against Rio Ave, a game the Lisbon giants won 2-1.
He shone over the 90 minutes and now United are thought to be looking at a £6m January deal for his services.
The Red Devils and Sporting have conducted business on many occasions through the years, with the likes of Cristiano Ronaldo, Nani and Marcos Rojo having moved between the clubs.
United have also been linked with Estadio Jose Alvalade star William Carvalho.