Sporting Lisbon defender Paulo Oliveira says he is flattered by interest from Manchester United.
The 23-year-old has been in impressive form this season, helping his club to an unbeaten start to the league campaign.
United have now been linked with a January move for the centre-back and the Portugal international admits such news is pleasing.
“It’s a good sign,” Oliveira told Antena 1 when asked about interest from Louis van Gaal’s side.
“I do not know about the facts but above all, it’s good to know that your work is being assessed.
“I have to continue to work harder and not fall asleep.”