Arsene Wenger maintains he has seen a few weaknesses in Barcelona which Arsenal can "exploit" when the Gunners look to cause an upset and keep their Champions League dream alive in the Nou Camp on Tuesday night.
Arsenal head to Spain with a chance of progressing to the semi-finals after fighting back to 2-2 from 2-0 down when Barcelona had dominated for the first part of the match, leaving the Gunners ball-watching for large spells.
Wenger insists he has seen enough to believe Arsenal can get the result needed and he said: "We created chances, even in the first half when we were dominated. We have not only to defend against them, but use the ball better than we did in the first half - there are some ideas we have to exploit."
Arsenal battled to a 1-0 victory over 10-man Wolves at Emirates Stadium on Saturday, where a stoppage-time winner from Nicklas Bendtner finally ended the visitors' brave resistance.
Wenger praised the way his team - which included seven changes from the first leg - had dug deep to record a vital victory in the Barclays Premier League title race after what had been a draining European tie midweek.
But they will be without former Barcelona trainee Cesc Fabregas, who suffered a crack to his leg bone when winning and scoring the penalty which levelled the tie last week.
Arsenal will check on the fitness of midfielder Alex Song (groin) and also whether veteran centre-back Sol Campbell can handle another big game with such a short recovery time.
Bendtner came off the bench against Wolves, and is expected to be restored to the starting XI on Tuesday. The big Dane - who netted a hat-trick in the last round against Porto - insists Arsenal are a side who never know when they are beaten.
"The belief and character we have showed in all the games is why got so many goals in the late stages," he said.
"We kept creating chance after chance and got what we deserved in the end, which was a victory. The most important thing was the three points and to then think about Barcelona."