The 26 years old man left the pitch after twisting his foot and the club said initial examinations revealed a “reactivation of the lesion of the fifth right metatarsal”, adding that treatment would depend on how the injury heals in the next few days.
He had fractured the same metatarsal last February and required surgery that effectively ended his club campaign. He returned to action in May, in time for the World Cup in Russia.
“Neymar is worried, because it’s the same foot, the right foot, in the same area,” PSG manager Thomas Tuchel told reporters.
The manager has criticised the referee for not protecting the Brazilian when Strasbourg’s players repeatedly fouled him.
“The referee didn’t whistle on one occasion, then two, then three and after that he ended up twisting his foot,” he added.
PSG will visit United at Old Trafford for the first leg of the Champions League round of 16 clash on Feb. 12.
PSG, who hold a 13-point lead in Ligue 1 with 53 points from 19 games, return to league action on Sunday when they host Rennes.