Gabriel has been out of action with a minor hamstring injury in recent weeks and although the defender is closing in on a return, he will miss this week’s showdown with the Spanish giants.
Meanwhile, Cazorla and Wilshere are long-term absentees and are not due to make their returns this month.
Speaking at a news conference at Arsenal’s London Colney training ground on Monday afternoon, Wenger said: “We are still without Wilshere, Cazorla and Gabriel. Everyone else is available.”
Arsenal head into Tuesday’s game on the back of their frustrating goalless draw with Hull City in the fifth round of the FA Cup on Saturday.
The north London side, who are third in the Premier League and two points off top spot, are bidding to reach the quarter-finals of Europe’s elite club competition for the first time since 2010.
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