Wenger suggested he may start the second leg with Chamakh, who played 28 minutes on Saturday against Sunderland, as his lone forward in preference to Nicklas Bendtner in that role and in the absence of the injured Robin van Persie.
"Marouane's getting back to his best, and getting sharper," the manager said. "We'll make some changes for Tuesday, that's for sure. We need some fresh legs for the Nou Camp because we'll have to run a lot there.
"We've not got enough security just to sit back and defend; you can't go to Barcelona and play for a 0-0. Anyway, it's not the personality of my team. This game has been hanging a bit over the heads of my players but our focus is on it now."