Arsenal will be without Gabriel on Saturday when they host Hull in the FA Cup fifth round.
Laurent Koscielny's involvement is also in doubt, but Arsene Wenger is optimistic the defender will be available.
"Koscielny is doing well," said Wenger. "He has a test this morning and he looks positive."
On Gabriel, he said: "He is running outside [but] he is out for Saturday."
There is better news regarding January signing Mohamed Elneny, though, who could get his second start at the Emirates.
"Elneny is fit," said Wenger. "He is one of the players who could get a run [out] there. He’s mobile, he’s a very good player. He’s adapting at the moment and I think he’s there now.
"We’ll certainly see him against Hull. He has a chance to start."
When asked about the extent to which he would rotate for the game, Wenger told the club's website: "I will, as always, play a team who has a good chance to qualify.
"The normal squad is involved on Saturday. It is a normal squad and we’ll play a usual strong team."