Sporting has reacted angrily after William Carvalho returned from international duty with Portugal with a fractured tibia.
The midfielder formed a key part of Portugal's run to the final at the UEFA European Under-21 championship where his side was beaten on penalties by Sweden.
However, the highly-rated 23-year-old - linked with Premier League side Arsenal - has reported back to his club with a fractured tibia, with Sporting suggesting he was made to play with the injury.
"Sporting hereby express their indignation that footballer William Carvalho has returned from his work with the under-21s team with a stress fracture in the tibia," a statement from the club read.
"Only yesterday, Monday, on the return of William Carvalho to training did the medical staff of Sporting Clube de Portugal identify a problem with the player and, curiously, only today at dawn did the Portuguese Football Federation send the Sporting Clube de Portugal clinic newsletters regarding the seven Sporting players who participated in the Under-21 European Championship.
"The clinical report from the Seleccao, referring to player William Carvalho, says the player never had any physical problem. The player denies this and says that the clinical department was aware of the player's complaints.
"As a result, the player William Carvalho faces between ten to 12 weeks out."