Roma continue to be plagued by injuries, with Paulo Dybala, Sardar Azmoun and Renato Sanches absent, with Houssem and Aouar limping off with a hamstring problem against Milan.
Ouar was part of the starting XI for tonight’s Serie A clash at the Stadio Olimpico.
The former Olympique Lyonnais midfielder lasted only 31 minutes when he collapsed and was asked to be substituted.
According to Sky Sport Italia and DAZN, Auer felt a pinch in the flexor of his left thigh and will undergo tests in the coming days to determine the extent of the damage.
He was replaced by Lorenzo Pellegrini, who was unable to start due to a minor hamstring problem.
Dybala and Azmoun were also not on the bench tonight as La Joya has not recovered from a groin problem sustained in the 2-1 defeat to Verona.
Renato Sanchez has also suffered a hamstring injury and is out until after the break on international duty, while Tammy Abraham and Marsh Kumbulla are out for long periods with torn anterior cruciate ligaments.