He suffered a bruised right knee ahead of next week’s Las Palmas match.
Nekounam will undergo a medical test on Wednesday at the San Miguel de Pamplona Clinic to determine the extent of his injury.
The development came a few weeks before the start of Asian Cup.
Iran football team has been drawn in group C along with Bahrain, UAE and Qatar in the 2015 AFC Asian Cup, which will be held in Australia from January 9 to 31.