Mikel Arteta provided the latest team news update in his pre-RC Lens press conference on Tuesday.
Fabio Vieira, who is currently serving a suspension for a red card in the Premier League, is allowed to play in the UEFA Champions League, but will miss Wednesday's match as "he’s been having some discomfort and we tried to have alternative treatment with him, and he wasn’t improving so we’ve sent him to see a specialist and that was to get an operation done in his groin, and we did that yesterday," Mikel said.
"We’re expecting him to be out for weeks now.