Middlesbrough boss Gareth Southgate was delighted with the form of winger Marvin Emnes in this week's friendly against Darlington.
He told Boro's website: "The supporters who came have seen the first glimpse of Marvin in this country, which I think they'll have been impressed with.
"He's one we've bought for the future but we're very impressed with what he's done in pre-season. He showed flashes of what we think is a very exciting talent. His quality is good but his endeavour and attitude are very good as well."