The Paris Saint-Germain captain was withdrawn during the first half during the 1-0 win over Lorient but his boss says the knock is not too serious.
The Brazilian center back was forced off in the first half after he collided with a Lorient player as les Parisiens scraped past Christian Gourcuff’s side through Thiago Motta’s first-half strike.
But Blanc said the injury is being dealt with and does not feel it is too bad.
“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.”
The 48-year-old admitted Lorient put up a good fight in Friday's match and was relieved to secure the win and stretch his side’s lead at the top of Ligue 1 to 11 points.
“We had a tough game. Especially in the first period because we had to adapt to the synthetic pitch. And then there is the quality of Lorient, who are a team that likes to play fast, passing football.
“We missed the opportunity to get a second goal that would have given us some breathing space. This is a good win, because it is always difficult here, especially against a team in form and motivated to fight.
“We were not great but we did what was necessary to get a hard-fought victory.”
Blanc was then asked if he will renew his contract with PSG and the former France international admits it could be tied up in the near future.
“It's being discussed but it is not yet done. This could be done quickly.”