The Czech midfielder took a heavy tackle from Wolverhampton Wanderers' Karl Henry on Saturday for which the Wolves man was, in the view of some observers rather harshly, awarded a red card.
But the effects of the challenge - visable for all to see - are still being felt by the Arsenal man, according to his manager, who rated his midfielder's chance of playing against Barca as "50-50".
"We will see about him tomorrow," Wenger told reporters at his Monday press conference.
"When you look at his calf, you can see the tackle of Henry was not as innocent as it looked."
The Gunners chief also refused to be drawn into yet another controversy about the tackle, and insisted that his player's focus had to be on Barcelona.
"I let people talk. We have to focus on this game rather than answer the critics," he asserted.
"We are used to that. No matter what happens, we always get that. We have to focus on this game."
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