Gallas doubtful for Barcelona first leg
"He will play some part before the end of the season, but will he be ready to play against Barcelona? I would say he is already at 80 percent out for the first leg," manager Arsene Wenger told the club website.
The former team captain, who has been sidelined since Feb. 10, has already been ruled out of the next two Premier League games against West Ham United and Birmingham.
Arsenal host European champions Barcelona on March 31 before travelling to the Nou Camp for the return leg on April 6.