Villarreal forward Nihat Kahveci could be out for up to four months after undergoing a successful operation on his right thigh.
The 28-year-old sustained the injury to his thigh in Turkey's quarter-final victory over Croatia at Euro 2008.
Nihat played a key role in Turkey's run through to the last four and scored twice in the dramatic 3-2 win against Czech Republic in Group A.
He was unable to play a part in the semi-final as Turkey lost 3-2 to Germany.
Nihat may now miss Turkey's first four World Cup qualifiers, which begin in the autumn.
The news will come as a major blow to Villarreal as they prepare for the new Primera Liga season and a UEFA Champions League campaign.
If his recovery takes as long as expected he will not be fit to return until the start of November.