Arsenal manager Arsene Wenger has confirmed that defender Gabriel Paulista is in the squad to face Monaco on Tuesday night.
Midfielders Tomas Rosicky and Alex Oxlade-Chamberlain are still ruled out.
The Frenchman also raised concerns over the condition of the Stade Louis II.
"It is a little bit [of a concern] - it has rained a lot," he said on Monday.
"There were two problems when I was a manager here. The quality of the pitch is not fantastic. When it rains in the south of France, it rains. It doesn't drizzle. They had to postpone a game recently because of the rain."
Asked about the possibility of 1-3 scoreline and a penalty shoot-out to decide the tie, the Arsenal boss added: "We practice penalties all year but not especially for tomorrow's game.
"You never know who finishes the game so we don't have an order. You have to improvise always a little bit."
