Atletico Madrid striker Luciano Vietto has been slated in Argentina as he prepares to leave the LaLiga.
The forward is on the brink of signing for Sporting CP.
Former Racing Club vice-president Pablo Podesta told A Bola that Sporting must be wary of who they're signing.
He claimed: "He is very good at deciding and dribbling, although he is not very strong physically, he is intelligent, he understands the game, he is skillful and he has a good technique.
"But when he has a player in front of him he has difficulties trying to get rid of him."
He added: "There's some problems in terms of character and personality, which is probably why (Diego) Simeone hasn't used him for Atletico Madrid."