The agent of Douglas Costa admits Manchester United retain interest in the Shakhtar Donetsk attacking midfielder.
United boss Sir Alex Ferguson has been following Douglas Costa since he first broke into the first team at Gremio.
Cesar Bottega told Calciomercatoweb.it: "At Manchester United, they have liked him for a long time. Napoli are also interested.
"If an interesting offer is made, then his club will consider it. But it will have to be an important one to convince them to sell as he is a major player for them."
