The Brazil international was forced off in the first half after colliding with an opposition player, which Blanc confirmed was a "nasty blow".
The French giants were paired with Chelsea in the quarter-final of the Champions League on Friday, but the 48-year-old is confident that the injury sustained will not affect his captain's participation in the tie.
"He has a big bump and ice was put on it," Blanc told beIN Sport. "He received a nasty blow. Let's call a spade a spade. When you jump like that, with the elbow, it hurts.
"But it is nothing serious. I hope anyway."
Les Parisiens moved nine points clear of second-placed Monaco in the Ligue 1 table following Friday's win.