Sporting Lisbon striker Ricky van Wolfswinkel is delighted with the way he has taken to Portuguese football.
"I came to Portugal eager to improve my football at all levels," said Van Wolfswinkel. "I am now much stronger physically.
"The competition in Portugal is much more intense, and I always have to be at my best."
United are expected to leave Van Wolfswinkel at Sporting for this season before assessing whether to buy the player in the summer.