Manchester United have been told that Porto winger James Rodriguez has a "concrete offer" from another club.

The Red Devils have been linked with a move for the 20-year-old, who has impressed during his time in Portugal.

However, the player's agent Silvio Sandri has now revealed that an unnamed club have emerged as rivals for his signature.

"Currently there is a concrete offer for the player," Sandri told Maisfutebol. "But I do know that United are interested too. Several scouts have made the trip to Porto to see James and have asked questions.

"We must await developments and on the offer itself, I don't have much else to say. The life of James has been based on small steps and playing it safe. Now he is happy at Porto and progressing a lot."

Rodriguez moved to the Portuguese champions from Argentine side Atletico Banfield in 2010.