The French giants host the Gunners at Parc des Princes in Group A on Tuesday night and Emery is hoping the Brazilian defender is ready for action having not played since a pre-season friendly against Real Madrid.
"Big matches are for big players," Emery said.
"We will decide after the final training session. We will see how he feels.
"The most important thing is if he feels ready. He is a big player. If he feels good, it is a possibility."